XXII. CHROMIDES AND PHARYNGOGNATHI

=SUBORDER Chromides.=—The suborder Chromides contains spiny-rayed fishes similar to the perch-like forms in most regards, but strikingly distinguished by the complete union of the lower pharyngeal bones, as in the Holconoti and Pharyngognathi, and still more remarkably by the presence of but one nasal opening on each side. In all the perch-like fishes and in nearly all others there are two nasal openings or nostrils on each side, these two entering into the same nasal sac. In all the Chromides the lateral line is incomplete or interrupted, and the scales are usually large and ctenoid.

=The Cichlidæ.=—The suborder Chromides includes two families, Cichlidæ, and Pomacentridæ. The Cichlidæ are fresh-water fishes of the tropics, characterized by the presence of three to ten spines in the anal fin. In size, color, appearance, habits, and food value they bear a striking resemblance to the fresh-water sunfishes, or Centrarchidæ, of the eastern United States. This resemblance is one of analogy only, for in structure the Cichlidæ have no more in common with the Centrarchidæ than with other families of perch or bass. The numerous species of Cichlidæ are confined to tropical America and to corresponding districts in Africa and western Asia. Tilapia nilotica abounds in the Nile. Tilapia galilæa is found in the river Jordan and the Lake of Galilee. This species is supposed to form part of the great draught of fishes recorded in the Gospels, and a black spot on the side is held to commemorate the touch of Simon Peter. Numerous other species of Cichlidæ, large and small, abound in central Africa, even in the salt ditches of the Sahara.

The species of Cichla, especially Cichla ocellaris, of the rivers of South America, elongate and large-mouthed, bear a strong analogy to the black bass of farther north. A vast number of species belonging to Heros, Acara, Cichlasoma, Geophagus, Chætobranchus, and related genera swarm in the Amazon region. Each of the large rivers of Mexico has one or more species; one of these, Heros cyanoguttatus, occurs in the Rio Grande and the rivers of southern Texas, its range corresponding with that of Tetragonopterus argentatus, just as the range of the whole family of Cichlidæ corresponds with that of the Characinidæ. No other species of either family enters the United States. A similar species, Heros tetracanthus, abounds in the rivers of Cuba, and another, Heros beani, called the mojarra verde, in the streams of Sinaloa. In the lakes and swamps of Central America Cichlidæ and Characinidæ are very abundant. One fossil genus is known, called Priscacara by Cope. Priscacara clivosa and other species occur in the Eocene of Green River and the Great Basin of Utah. In this genus vomerine teeth are said to be present, and there are three anal spines. None of the living Cichlidæ have vomerine teeth.

=The Damsel-fishes: Pomacentridæ.=—The Pomacentridæ, called rock-pilots or damsel-fishes, are exclusively marine and have in all cases but two anal spines. The species are often very brilliantly colored, lustrous metallic blue and orange or scarlet being the prevailing shades among the bright-colored species. Their habits in the reef pools correspond very closely with those of the Chætodontidæ. With the rock-pilots, as with the butterfly-fishes, the exceeding alertness and quickness of movement make up for lack of protective colors. With both groups the choice of rocky basins, crevices in the coral, and holes in coral reefs preserves them from attacks of enemies large enough to destroy them. In Samoa the interstices in masses of living coral are often filled with these gorgeous little fishes. The Pomacentridæ are chiefly confined to the coral reefs, few ranging to the northward of the Tropic of Cancer. Sometimes the young are colored differently from the adult, having sky-blue spots and often ocelli on the fins, which disappear with age. But one species Chromis chromis, is found in the Mediterranean. Chromis punctipinnis, the blacksmith, is found in southern California, and Chromis notatus is the common dogoro of Japan. One of the largest species, reaching the length of a foot, is the Garibaldi, Hypsypops rubicundus, of the rocky shores of southern California. This fish, when full grown, is of a pure bright scarlet. The young are greenish, marked with blue spots. Species of Pomacentrus, locally known as pescado azul, abound in the West Indies and on the west coast of Mexico. Pomacentrus fuscus is the commonest West Indian species, and Pomacentrus rectifrenum the most abundant on the west coast of Mexico, the young, of an exquisite sky-blue, crowding the rock pools. Pomacentrus of many species, blue, scarlet, black, and golden, abound in Polynesia, and no rock pool in the East Indies is without several forms of this type. The type reaches its greatest development in the south seas. About forty different species of Pomacentrus and Glyphisodon occur in the corals of the harbor of Apia in Samoa.

Almost equally abundant are the species of Glyphisodon. The "cockeye pilot," or jaqueta, Glyphisodon marginatus, green with black bands, swarms in the West Indies, occasionally ranging northward, and is equally common on the west coast of Mexico. Glyphisodon abdominalis replaces it in Hawaii, and the Asiatic Glyphisodon saxatilis is perhaps the parent of both. Glyphisodon sordidus banded with pale and with a black ocellus below the soft dorsal is very common from Hawaii to the Red Sea, and is a food-fish of some importance. Glyphisodon cœlestinus blue, with black bands, abounds in the south seas.

The many species of Amphiprion are always brilliant, red or orange, usually marked by one or two cross-bands of creamy blue. Amphiprion melanopus abounds in the south seas. Azurina hirundo is a slender species of lower California of a brilliant metallic blue. All these species are carnivorous, feeding on shrimps, worms, and the like.

Microspathodon is herbivorous, the serrated incisors being loosely implanted in the jaws. Microspathodon dorsalis, of the west coast of Mexico, is of a deep indigo-blue color, with streamer-like fins. Microspathodon chrysurus, of the West Indian coral reefs, black with round blue spots and the tail yellow. This family is probably of recent origin, as few fossils are referred to it. Odonteus pygmæus of the Eocene perhaps belongs to it.

=Suborder Pharyngognathi.=—The wrasses and parrot-fishes, constituting the group called Pharyngognathi (φαρύγξ, gullet; γνάθος, jaw), by Johannes Müller, have the lower pharyngeal bones much enlarged and solidly united, their teeth being either rounded or else flat and paved. The nostrils, ventral fins, pectoral fins and shoulder-girdle are of the ordinary perch-like type. The teeth are, however, highly specialized, usually large and canine-like, developed in the jaws only, and the gills are reduced in number, 3½ instead of 4, with no slit behind the last half gill. The scales are always cycloid and are usually large. In the tropical forms the vertebræ are always twenty-four in number (10 + 14), but in northern forms the number is largely increased with a proportionate increase in the number and strength of the dorsal spines. All the species are strictly marine, and the coloration is often the most highly specialized and brilliant known among fishes, the predominant shade being blue.

All are carnivorous, feeding mainly on crustaceans and snails, which they crush with their strong teeth, there being often a strong canine at the posterior end of the premaxillary, which holds the snail while the lower jaw acts upon it. The species are very numerous and form the most conspicuous feature in the fish markets of every tropical port. They abound especially in the pools and openings in the coral reefs. All are good for food, though all are relatively flavorless, the flesh being rather soft and not oily.

=The Wrasse Fishes: Labridæ.=—The principal family is that of the Labridæ, characterized by the presence of separate teeth in the front of the jaws. Numerous fossil species are known from the Eocene and Miocene. Most of these are known only from the lower pharyngeal bones. Labrodon is the most widely diffused genus, probably allied to Labrus, but with a pile of successional teeth beneath each functional tooth. The species are mostly from the Miocene.

The northern forms of Labridæ are known as wrasse on the coasts of England. Among these are Labrus bergylta, the ballan wrasse; Labrus viridis, the green wrasse; Labrus ossiphagus, the red wrasse; and Labrus merula, the black wrasse. Acantholabrus palloni and Centrolabrus exoletus have more than three anal spines. The latter species, known as rock cook, is abundant in western Norway, as far north as Throndhjem, its range extending to the northward beyond that of any other Labroid. Allied to these, on the American coast, is the tautog or blackfish, Tautoga onitis, a common food-fish, dusky in color with excellent white flesh, especially abundant on the coast of New England. With this, and still more abundant, is the cunner or chogset, Tautogolabrus adspersus, greenish-blue in color, the flesh being also more or less blue. This fish is too small to have much value as food, but it readily takes the hook set for better fishes.

In the Mediterranean are found many species of Crenilabrus, gaily colored, each species having its own peculiar pattern and its own arrangement of inky spots. Among these are Crenilabrus mediterraneus, Crenilabrus pavo, and Crenilabrus griseus. With these are the small species called Ctenolabrus rupestris, the goldsinny, much like the American cunner, and the long-nosed Symphodus scina.

Of the many West Indian species we may notice the Capitaine or hogfish, Lachnolaimus maximus, a great fish, crimson in color, with its fin spines ending in long streamers; Bodianus rufus, the Spanish ladyfish or pudiano, half crimson, half golden. Halichæres radiatus, the pudding-wife (a mysterious word derived from "oldwife" and the Portuguese name, pudiano), a blue fish handsomely mottled and streaked. Of the smaller species, Clepticus parræ, the janissary, with very small teeth, Halichœres bivittatus, the slippery-dick, ranging northward to Cape Hatteras, and Doratonotus megalepis, of an intense grass-green color, are among the most notable. The razor-fish, Xyrichthys psittacus, red, with the forehead compressed to a sharp edge, is found in the Mediterranean as well as throughout the West Indies, where several other species of razor-fish also occur.

Scarcely less numerous are the species of the Pacific Coast of America. Pimelometopon pulcher, the redfish or fathead of southern California, reaches a length of two feet or more. It abounds in the broad band of giant kelp which lines the California coast and is a food-fish of much importance. The female is dull crimson. In the male the head and tail are black and on the top of the head is developed with age a great adipose hump. A similar hump is found on the adult of several other large labroids. Similar species on the coast of South America, differing in color and size of scales, are Pimelometopon darwini, Trochocopus opercularis, and Bodianus diplotænia. The señorita, Oxyjulis californica, is a dainty cream-colored little fish of the California coast, Halichœres semicinctus, the kelpfish, light olive, the male with a blue shoulder bar, is found in southern California. On the west coast of Mexico are numerous species of Thalassoma, Halichœres, Pseudojulis, Xyrichthys and Iniistius, all different from the corresponding species in the West Indies, and equally different from the much greater variety found in Hawaii and in Samoa. About the Polynesian and West Indian islands abound a marvelous wealth of forms of every shade and pattern of bright colors—blue, green, golden, scarlet, crimson, purple—as if painted on with lavish hand and often in the most gaudy pattern, although at times laid on with the greatest delicacy. The most brilliant species belong to Thalassoma and Julis, the most delicately colored to Stethojulis and Cirrhilabrus. In Gomphosus the snout is prolonged on a long slender tube. In Cheilio the whole body is elongate. In Iniistius the first two dorsal spines form a separate fin, the forehead being sharp as in Xyrichthys. Other widely distributed genera are Anampses, Lepidaplois, Semicossyphus, Duymæria, Platyglossus, Pseudolabrus, Hologymnosus, Macropharyngodon, Coris, Julis, Hemipteronotus, Novaculichthys, Cheilinus, Hemigymnus, and Cymolutes. Halichœres is as abundant in the East Indies as in the West, one of its species Halichœres pæcilopterus being common as far north as Hakodate in Japan. In this species as in a few others the sexes are very different in color, although in most species no external sexual differences of any sort appear. In the East Indian genus, Pseudocheilinus, the eye is very greatly modified. The cornea is thickened, forming two additional lens-like structures.

The small family of Odacidæ differs from the Labridæ in having in each jaw a sharp cutting edge without distinct teeth anteriorly, the pharyngeal teeth being pavement-like. The scales are small, very much smaller than in the Scaridæ, the body more elongate, and the structure of the teeth different. The species are mostly Australian, Odax balteatus being the most abundant. It is locally known as kelpfish.

In the Siphonognathidæ the teeth are much as in the Odacidæ, but the body is very elongate, the snout produced as in the cornet-fishes (Fistularia), and the upper jaw ends in a long skinny appendage. Siphonognathus argyrophanes, from Australia, reaches a length of sixteen inches.

=The Parrot-fishes: Scaridæ.=—The parrot-fishes, or Scaridæ, are very similar to the Labridæ in form, color, and scales, but differ in the more or less complete fusion of the teeth, a character which varies in the different genera.

Of these the most primitive is Calotomus, confined to the East Indies and Polynesia. In this genus the teeth are united at base, their tips free and imbricated over the surface of the jaw.

The species are dull in color, reddish or greenish. Calotomus japonicus is the Budai or Igami of Japan. Calotomus sandwichensis and Calotomus irradians are found in Hawaii, and Calotomus xenodon on the off-shore islands of Mexico. In Calotomus the dorsal spines are slender. In Scaridea (balia) of the Hawaiian Islands the first dorsal is formed of pungent spines as in Sparisoma.

Cryptotomus of the Atlantic is also a transitional group having the general characters of Sparisoma, but the anterior teeth more separate. The several species are all small and characteristic of the West Indian fauna, one species, Cryptotomus beryllinus, ranging northward to Long Island.

In the large genus Sparisoma the teeth are more completely joined. In this group, which is found only in the tropical Atlantic, the lower pharyngeals are broader than long and hexagonal. The teeth of the jaws are not completely united, the dorsal spines are pungent, the lateral line not interrupted, and the gill membranes broadly united to the isthmus.

Of the numerous species the dull-colored Sparisoma flavescens is most abundant in the West Indies and ranges farther north than any other. Sparisoma cretense, the Scarus of the ancients, is found in the Mediterranean, being the only member of the family known in Europe and the only Sparisoma known from outside the West Indian fauna.

Other West Indian species are the red parrot-fish, Sparisoma abildgaardi, Sparisoma xystrodon, Sparisoma hoplomystax, the last two being small species about the Florida Keys, and the handsome Sparisoma viride from the West Indies.

Scarus is the great central genus of parrot-fishes. Its members are especially abundant in Polynesia and the East Indies, the center of distribution of the group, although some extend their range to western Mexico, Japan, the Red Sea, and Australia, and a large number are found in the West Indies. Most of them are fishes of large size, but a few, as the West Indian Scarus croicensis, reach the length of less than a foot, and other still smaller species (Scarus evermanni, Scarus bollmani) are found only in water of considerable depth (200 fathoms).

The genus Scarus is characterized by not only the almost complete fusion of its teeth, but by numerous other characters. Its lower pharyngeals are oblong and spoon-shaped, the teeth appearing as a mosaic on the concave surface. The gill-membranes are scarcely united to the narrow isthmus, the lateral line is interrupted, the dorsal spines are flexible, and there are but few scales on the head. These, as well as the scales of the body, are always large. The most highly specialized of its species have the teeth deep blue in color, a character which marks the genus or subgenus Pseudoscarus. Of the species of this type, the loro, Pseudoscarus cœlestinus, and the more abundant guacamaia, Pseudoscarus guacamaia (fig. 215 vol. I) of the West Indies, are characteristic forms. The perrico, Pseudoscarus perrico of the west coast of Mexico, and the great blue parrot-fish, or galo, of Hawaii and Samoa, Pseudoscarus jordani, belong to this type. Pseudoscarus jordani was formerly tabu to the king in Hawaii, and its brilliant colors and toothsome flesh (when eaten raw) made it the most highly valued fish at the royal banquets of old Hawaii. It still sells readily at a dollar or more per pound. To this type belong also the blue parrot-fish, Pseudoscarus ovifrons, of Japan. In the restricted genus Scarus proper the teeth are pale. The great blue parrot-fish, of the West Indies, Scarus cœruleus, belongs to this group. This species, deep blue in color, reaches a large size, and the adult has a large fleshy hump on the forehead. Lesser parrot-fish with pale teeth and with showy coloration are the West Indian species Scarus tæniopterus, Scarus vetula, Scarus croicensis, etc.

Very many species of both Scarus and Pseudoscarus, green, blue, red-brown, or variegated, abound about the coral reefs of Polynesia. About twenty-five species occur in Samoa. Pseudoscarus latax and P. ultramarinus being large and showy species, chiefly blue. Pseudoscarus prasiognathus is deep red with the jaws bright blue.

Fossil species referred to Scarus but belonging rather to Sparisoma are found in the later Tertiary. The genera Phyllodus, Egertonia, and Paraphyllodus of the Eocene perhaps form a transition from Labridæ to Scaridæ. In Paraphyllodus medius the three median teeth of the lower pharyngeals are greatly widened, extending across the surface of the bone.

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XXIII. THE SQUAMIPINNES

=The Squamipinnes.=—Very closely allied to the Percomorphi is the great group called Squamipinnes (squama, scale; pinna, fin) by Cuvier and Epelasmia by Cope. With a general agreement with the Percomorphi, it is distinguished by the more or less complete soldering of the post-temporal with the cranium. In the more specialized forms we find also a soldering of the elements of the upper jaw, and a progressive reduction in the size of the gill-opening. The ventral fin retains its thoracic insertion, and, as in the perch mackerel-like forms, it has one spine and five rays, never any more. The ventral fins are occasionally lost in the adult, as in the Stromateidæ, or they may lose part of their rays. The name Squamipinnes refers to the scaly fins, the typical species having the soft rays of dorsal, anal, and caudal, and sometimes of other fins densely covered with small scales. In various aberrant forms these scales are absent. The name Epelasmia (ἔπι, above; ἐλάσμος, plate) refers to the thin upper pharyngeals characteristic of certain forms. The transition from this group to the Sclerodermi is very clear and very gradual. The Squamipinnes, Sclerodermi, Ostracodermi, and Gymnodontes form a continuous degenerating series. On the other hand the less specialized Squamipinnes approach very closely to forms already considered. The Antigoniidæ are of uncertain affinities, possibly derived from such forms as Histiopteridæ, while Platax show considerable resemblance to scaly-finned fishes like the Kyphosidæ and Stromateidæ. The Scorpididæ seem intermediate between Stromateidæ and Platacidæ. In such offshoots from Scombroidei or Percoidei the group doubtless had its origin.

We may begin the series with some forms which are of doubtful affinity and more or less intermediate between the Squamipinnes and the more primitive Percomorphi.

=The Scorpididæ.=—This family has the general appearance of Platax and Ilarches, but the teeth are not brush-like, and the post-temporal is free from the skull as in perch-like fishes. The species inhabit the Pacific. Scorpis georgianus is a food-fish of Australia, with the body oblong. Monodactylus argenteus, the toto of Samoa, is almost orbicular in form, while Psettus sebæ is twice as deep as long, the deepest-bodied of all fishes in proportion to its length.

=The Boarfishes: Antigoniidæ.=—The boarfishes (Antigoniidæ) are characterized by a very deep body covered with rough scales, the post-temporal, as in the Chætodontidæ and the Zeidæ, being adnate to the skull.

These fishes bear some resemblance to Zeus, but there is no evidence of close affinity nor is it clear that they are related to the Chætodontidæ. Capros aper, the boarfish, is common in southern Europe, reaching a length of less than a foot, the protractile mouth suggesting that of a pig. The diamond-fishes, Antigonia, are deeper than long and strongly compressed, the body being covered with roughish scales. The color is salmon-red and the species live just below the depths ordinarily explored by fishermen. Antigonia capros is found at Madeira and in the West Indies, Antigonia steindachneri about Hawaii and in Japan, while the smaller Antigonia rubescens is abundant in the Japanese bays at a depth reached by the dredge. An extinct genus, Proantigonia from the Miocene is said to connect Antigonia with Capros.

=The Arches: Toxotidæ.=—The archers, Toxotidæ, have the body compressed, the snout produced, and the dorsal fin with but five spines. The skeleton differs widely from that of Chætodon and the family should perhaps rather find its place among the percoids. Toxotes jaculatrix is found in the East Indies. The name alludes to its supposed habit of catching insects by shooting drops of water at them through its long mouth.

=The Ephippidæ.=—With the typical Squamipinnes, the teeth become very slender, crowded in brush-like bands. The least specialized family is that of Ephippidæ, characterized by the presence of four anal spines and a recumbent spine before the dorsal. The principal genus, Ephippus (Scatophagus), is represented by Ephippus argus, a small, bass-like fish, spotted with black, found in the Indian seas, and ranging northward to Formosa. Species referred to Ephippus (Scatophagus) are recorded from the Italian Eocene of Monte Bolca, where a species of Toxotes has been also found.

=The Spadefishes: Ilarchidæ.=—In the Ilarchidæ the dorsal is divided into two fins, the spinous part being free from scales. In various regards the species are intermediate between ordinary perch-like forms and the chætodonts. In these fishes the body is very deep and, with the soft fins, closely covered with roughish scales. In Ilarches (Ephippus), represented by Ilarches orbis of the Indian seas, these scales are relatively large. This species is a common food-fish from India to Formosa.

In the American genus, Chætodipterus, the scales are quite small. The spadefish (Chætodipterus faber), sometimes called also moonfish or angel-fish, is a large, deep-bodied fish, reaching a length of two feet. It is rather common from Cape Cod to Cuba, and is an excellent pan fish, with finely flavored white flesh. The young are marked by black cross-bands which disappear with age, and in the adult the supraoccipital crest is greatly thickened and the skull otherwise modified. A very similar species, Chætodipterus zonatus, occurs on the west coast of Mexico. Species allied to Chætodipterus are fossil in the Italian Eocene. The Drepanidæ of the East Indies are close to the Ilarchidæ. Drepane punctata is a large, deep-bodied fish resembling the spadefish but with larger scales.

=The Platacidæ.=—Closely related to the Ilarchidæ is also the East Indian family of Platacidæ, remarkable for the very great depth and compression of the body, which is much deeper than long, and the highly elevated dorsal and anal still further emphasize this peculiarity of form. In this group the few dorsal spines are closely attached to the soft rays and the general color is dusky. In the young the body is deeper than in the adult and the ventral fins much more produced. The best-known species is the tsuzume or batfish (Platax orbicularis), which ranges from India through the warm current to northern Japan. Platax teira, farther south, is very similar. Platax altissimus, with a very high dorsal, is a fossil in the Eocene of Monte Bolca.

=The Butterfly-fishes: Chætodontidæ.=—The central family of Squamipinnes is that of the butterfly-fishes or Chætodontidæ. In this group the teeth are distinctly brush-like, the mouth small, the dorsal fin continuous and closely scaly, and the ventral fins with one spine and five rays. The species are mostly of small size and brilliant and varied coloration, yellow and black being the leading colors. They vary considerably with age, the young having the posterior free edges of the bones of the head produced, forming a sort of collar. These forms have received the name of Tholichthys, but that supposed genus is merely the young of Chætodon. The species of Chætodontidæ abound in rock pools and about coral reefs in clear water. They are among the most characteristic forms of these waters and their excessive quickness of movement compensates for their conspicuous coloration. In these confined localities they have, however, few enemies. The broad bodies and spinous fins make them rather difficult for a large fish to swallow. They feed on small crustaceans, worms, and the like. The analogy to the butterfly is a striking one, giving rise to the English name, butterfly-fish, the Spanish mariposa, and the Japanese chochouwo, all having the same meaning. Fossil chætodonts are rather few, Chætodon pseudorhombus of the Pliocene of France, Holocanthus microcephalus and Pomacanthus subarcuatus of the Eocene, being the only species recorded by Zittel.

In the principal genus, Chætodon, the colors are especially bright. There is almost always a black bar across the eye, and often black ocelli adorn the fins. This genus is wanting in Europe. Chætodon capistratus, striatus, and numerous other species are found in the West Indies; Chætodon humeralis and nigrirostris are common on the coast of Mexico. The center of their distribution is in Polynesia and the East Indian Archipelago. Chætodon reticulatus, lineolatus, ulietensis, ornatissimus, ephippion, setifer, and auriga are among the most showy species. Numerous closely related genera are described. In some of these the snout is prolonged into a long tube, bearing the jaws at its end. Of this type are Chelmo in India, Forcipiger in Polynesia, and Prognathodes in the West Indies. Heniochus (macrolepidotus) has one dorsal spine greatly elongated. Microcanthus strigatus, one of the most widely distributed species, is known by its small scales. Megaprotodon (triangularis) has four anal spines instead of three as in the others.

The species of Holacanthus, known as angel-fishes, are larger in size, and their colors are still more showy, being often scarlet or blue. In this genus the preopercle is armed with a strong spine, and there are fourteen or more strong spines in the dorsal. This genus has also its center of distribution in the East Indies, whence two species (septentrionalis and ronin) with concentric stripes of blue range northward to Japan. Holacanthus tibicen, jet-black with one yellow cross-band, is found from the Riu Kiu Islands southward. The angel-fish or isabelita (Holacanthus ciliaris), orange-red, sky-blue, and golden, as though gaudily painted, is the best-known species. The vaqueta de dos colores or rock beauty (Holacanthus bicolor), half jet-black, half golden, is scarcely less remarkable. Both are excellent food-fishes of the West Indies. Holacanthus passer is a showy inhabitant of the west coast of Mexico. Holacanthus diacanthus, orange, barred with blue, is one of the gaudiest inhabitants of the coral reefs of Polynesia. Holacanthus flavissimus, golden with some deep-blue markings, and Holacanthus nicobariensis, blackish with white circles, are found with other species in the same waters.

The genus Pomacanthus (Pomacanthodes) includes American species only, still larger in size and differing from Holacanthus in having nine to eleven spines only in the dorsal fin. The young of Pomacanthus are blackish, crossed by many curved yellow cross-bands, which disappear entirely with age. Three species are known, Pomacanthus arcuatus, the black angel, chirivita or portugais, Pomacanthus paru, the Indian-fish or paru of the West Indies, and Pomacanthus zonipectus, "Mojarra de las Piedras," of the west coast of Mexico. All are good food-fishes, but lacking the brilliant colors of Holacanthus and the fine pattern usual in Chætodon.

=The Pygæidæ.=—Between the Chætodontidæ and the Acanthuridæ we would place the extinct family of Pygæidæ, of the Eocene. In Pygæus gigas and other species the dorsal spines are strong and numerous; there are 5 to 8 species in the anal fin, the scales are shagreen-like, and the teeth seem coarser than in the Chætodontidæ. The tail is apparently unarmed, and the soft dorsal, as in Chætodon, is much shorter than the spinous. To this family the Eocene genera, Aulorhamphus (bolceusis), with produced snout, and Apostasis (croaticus), with long spinous dorsal, probably belong.

=The Moorish Idols: Zanclidæ.=—The family of Zanclidæ includes a single species, the Moorish idol or kihi kihi, Zanclus canescens. In this family the scales are reduced to a fine shagreen, and in the adult two bony horns grow out over the eye. The dorsal spines are prolonged in filaments and the color is yellow crossed by bars of black. Zanclus canescens is a very handsome fish with the general appearance and habit of a Chætodon, but the form is more exaggerated. It is found throughout Polynesia, from Japan to the off-shore islands of Mexico, and is generally common, though rarely entering rock pools.

Zanclus eocænus is recorded from the Italian Eocene.

=The Tangs: Acanthuridæ.=—In the next family, Acanthuridæ, the surgeon-fishes or tangs, the scales remain small and shagreen-like, the body is more elongate, the gill-openings still more restricted, and the teeth are flattened and incisor-like. The pubic bone is more elongate, and in all the species some sort of armature is developed on the side of the tail. The spinous dorsal in all is less developed than the soft dorsal. The species abound in the warm seas, especially about the tide pools, and are used as food. They undergo considerable changes with age, the caudal armature being developed by degrees. Nearly all are dull brown in color, but in some a vivid ornamentation is added. Fossil forms are found from the Eocene and later. Most of these are referable to Teuthis and Acanthurus.

The principal genus is Teuthis, characterized by the presence on each side of the tail of a sharp, knife-like, movable spine with the point turned forwards and dropping into a sheath. This spine gives these fishes their name of surgeon-fish, doctor-fish, lancet-fish, tang, barbero, etc., and it forms a very effective weapon against fish or man who would seize one of these creatures by the tail. The species have the center of distribution in the East Indies and have not reached Europe. Three species are found in the West Indies. The blue tang (Teuthis cœruleus) is chiefly bright blue. The common tang, Teuthis chirurgus, is brown with bluish streaks, while a third species, Teuthis bahianus, has a forked caudal fin. Very close to this species is Teuthis crestonis, of the west coast of Mexico, and both are closely related to Teuthis matoides, found from India to Hawaii.

Teuthis triostegus, of Japan and Polynesia and the East Indies, is covered with cross-bands alternately black and pale. In Hawaii this is replaced by the very similar Teuthis sandwichensis. Many species are found about Hawaii and the other Polynesian Islands. Teuthis achilles has a large blotch of brilliant scarlet on the tail, and Teuthis olivaceus a bright-colored mark on the shoulder. Teuthis lineatus, yellow with blue stripes, a showily colored fish of the coral reefs, is often poisonous, its flesh producing ciguatera.

Zebrasoma differs from Teuthis in having but 4 or 5 dorsal spines instead of 10 or 11. In this genus the soft dorsal fin is very high. Zebrasoma flavescens, sometimes brown, sometimes bright yellow, is common in Polynesia; Zebrasoma veliferum, cross-barred with black, is also common.

Ctenochætus (strigosus), unlike the others, is herbivorous and has its teeth loosely implanted in the gums. This species, black with dull orange streaks, was once tabu to the king of Hawaii, who ate it raw, and common people who appropriated it were put to death.

In Xesurus the caudal lancelet is replaced by three or four bony tubercles which have no sharp edge. Xesurus scalprum is common in Japan, and there are three species or more on the west coast of Mexico, Xesurus punctatus and Xesurus laticlavius being most abundant.

In Prionurus (microlepidotus) of the tropical Pacific the armature is still more degraded, about six small plates being developed.

In Acanthurus (Monoceros, Naseus), the unicorn-fish and its relatives, the ventral fins are reduced, having but three soft rays, the caudal spines are very large, blunt, immovable, one placed in front of the other. In most of the species of Acanthurus a long, bony horn grows forward from the cranium above the eye. This is wanting in the young and has various degrees of development in the different species, in some of which it is wholly wanting. The species of Acanthurus reach a large size, and in some the caudal spines are bright scarlet, in others blue. Acanthurus unicornis, the unicorn-fish, is the commonest species and the one with the longest horn. It is abundant in Japan, in Hawaii, and in the East Indies.

Axinurus thynnoides of the East Indies has a long, slim body, with slender tail like a mackerel.

=Suborder Amphacanthi, the Siganidæ.=—The Amphacanthi (ἄμφϊ, everywhere; ἄκανθα, spine) are spiny-rayed fishes certainly related to the Teuthididæ, but differing from all other fishes in having the last ray of the ventrals spinous as well as the first, the formula being I. 4, I. The anal fin has also six or seven spines; and the maxillary is soldered to the premaxillary. The skeleton is essentially like that of the Acanthuridæ.

The single family, Siganidæ, contains fishes of moderate size, valued as food, and abounding about rocks in shallow water from the Red Sea to Tahiti. The coloration is rather plain olive or brown, sometimes with white spots, sometimes with bluish lines. The species are very much alike and all belong to the single genus Siganus. One species, Siganus fuscescens, dusky with small, pale dots, is a common food-fish of Japan. Others, as Siganus oramin and Siganus vermiculatus, occur in India, and Siganus punctatus, known as lo, abounds about the coral reefs of Samoa. Siganus vulpinus differs from the others in the elongate snout.

A fossil genus, Archoteuthis (glaronensis), is found in the Tertiary of Glarus. It differs from Siganus in the deeper body and in the presence of six instead of seven spines in the anal fin.

The real relationship of the Siganidæ is still uncertain, but the family is probably most nearly allied to the Acanthuridæ, with which the species were first combined by Linnæus, who included both in his genus Teuthis. In the structure of the vertical fins the Siganidæ resemble the extinct genus Pygæus.

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XXIV. SERIES PLECTOGNATHI

=THE Plectognaths.=—Derived directly from the Acanthuridæ, from which they differ by progressive steps of degeneration, are the three suborders of Sclerodermi, Ostracodermi, and Gymnodontes, forming together the series or suborder of Plectognathi. As the members of this group differ from one another more widely than the highest or most generalized forms differ from the Acanthuridæ, we do not regard it as a distinct order. The forms included in it differ from the Acanthuridæ much as the swordfishes differ from ordinary mackerel. The Plectognathi (πλεϡτός, woven together; γνάθος, jaw) agree in the union of the maxillary and premaxillary, in the union of the post-temporal with the skull, in the great reduction of the gill-opening, and in the elongation of the pelvic bones. All these characters in less degree are shown in the Squamipinnes. We have also the reduction and final entire loss of ventral fins, the reduction and loss of the spinous dorsal, the compression and final partial or total fusion of the teeth of the upper jaw, the specialization of the scales, which change from bony scutes into a solid coat of mail on the one hand, and on the other are reduced to thorns or prickles and are finally altogether lost. The number of vertebræ is also progressively reduced until in the extreme forms the caudal fin seems attached to the head, the body being apparently wanting. Throughout the group poisonous alkaloids are developed in the flesh. These may produce the violent disease known as ciguatera, directly attacking the nervous system. See p. 182, vol. I.

The three suborders of plectognathous are easily recognized by external characters. In the Sclerodermi (σκλερός, hard; δέρμα, skin) the spinous dorsal is present and the body is more or less distinctly scaly. The teeth are separate and incisor-like and the form is compressed. In the Ostracodermi (ὀστράκος, a box; δέρμα, skin) there is no spinous dorsal, the teeth are slender, and the body is inclosed in an immovable, bony box. In the Gymnodontes (γυμνός, naked; ὀδούς, tooth) the teeth are fused into a beak like that of a turtle, either continuous or divided by a median suture in each jaw, the spinous dorsal is lost, and the body is covered with thorns or prickles or else is naked.

=The Scleroderms.=—The Sclerodermi include three recent and one extinct families. Of the recent forms, Triacanthidæ is the most primitive, having the ventral fins each represented by a stout spine and the skin covered with small, rough scales. The dorsal has from four to six stiff spines.

Triacanthodes anomalus is found in Japan, Hollardia hollardi in Cuba. Triacanthus brevirostris, with the first spine very large, is the common hornfish of the East Indies ranging northward to Japan.

=The Trigger-fishes: Balistidæ.=—The Balistidæ, or trigger-fishes, have the body covered with large rough scales regularly arranged. The first dorsal fin is composed of a short stout rough spine, with a smaller one behind it and usually a third so placed that by touching it the first spine may be set or released. This peculiarity gives the name of trigger-fish as well as the older name of Balistes, or cross-bow shooter. There are no ventral fins, the long pelvis ending in a single blunt spine. The numerous species of trigger-fishes are large coarse fishes of the tropical seas occasionally ranging northward. The center of distribution is in the East Indies, where many of the species are most fantastically marked. Balistes carolinensis, the leather-jacket, or cucuyo, is found in the Mediterranean as also on the American coast. Balistes vetula, the oldwife, oldwench, or cochino, marked with blue, is common in the West Indies, as are several other species, as Canthidermis sufflamen, the sobaco, and the jet-black Melichthys piceus, the black oldwife, or galafata. Several species occur on the Pacific Coast of Mexico, the Pez Puerco, Balistes verres, being commonest. Still others are abundant about the Hawaiian Islands and Japan. The genus Balistapus, having spinous plates on the tail, contains the largest number of species, these being at the same time the smallest in size and the most oddly colored. Balistapus aculeatus and Balistapus undulatus are common through Polynesia to Japan. Most of the tropical species of Balistidæ are more or less poisonous, causing ciguatera, the offensive alkaloids becoming weaker in the northern species. Melichthys radula abounds in Polynesia. In this species great changes take place at death, the colors changing from blue and mottled golden green to jet black. Other abundant Polynesian species are Xanthichthys lineopunctatus, Balistes vidua, Balistes bursa, and Balistes flavomarginatus.

=The File-fishes: Monacanthidæ.=—Closely related to the Balistidæ are the Monacanthidæ, known as filefishes, or foolfishes. In these the body is very lean and meager, the scales being reduced to shagreen-like prickles. The ventral fins are replaced by a single movable or immovable spine, which is often absent, and the first dorsal fin is reduced to a single spine with sometimes a rudiment behind it. The species are in general smaller than the Balistidæ and usually but not always dull in color. They have no economic value and are rarely used as food, the dry flesh being bitter and offensive. The species are numerous in tropical and temperate seas, although none are found in Europe. On our Atlantic coast, Stephanolepis hispidus and Ceratacanthus schœpfi are common species. In the West Indies are numerous others, Osbeckia lævis and Alutera güntheriana, largest in size, among the commonest. Both of these are large fishes without ventral spine. Monacanthus chinensis, with a great, drooping dewlap of skin behind the ventral spine, is found on the coast of China. Of the numerous Japanese species, the most abundant and largest is Pseudomonacanthus modestus, with deep-blue fins and the ventral spine immovable. Another is Stephanolepis cirrhifer, known as Kawamuki, or skin-peeler. Alutera monoceros, and Osbeckia scripta, the unicorn fish, abound in the East Indies, with numerous others of less size and note. In the male of the Polynesian Amanses scopas (Fig. 347) the tail is armed with a brush of extraordinarily long needle-like spines.

In Stephanolepis spilosomus the caudal fin is of a brilliant scarlet color, contrasting with the usual dull colors of these fishes. In Oxymonacanthus longirostris the body is blue with orange checker-like spots and the snout is produced in a long tube. About the islands of Polynesia, filefishes are relatively few, but some of them are very curious in form or color.

=The Spinacanthidæ.=—In the extinct family Spinacanthidæ the body is elongate, high in front and tapering behind. The first dorsal has six or seven spines, and there are rough spines in the pectoral. The teeth are bluntly conical. Spinacanthus blennioides and S. imperalis are found in the Eocene of Monte Bolca. These are probably the nearest to the original ancestor among known scleroderms.

=The Trunkfishes: Ostraciidæ.=—The group Ostracodermi contains the single family of Ostraciidæ, the trunkfishes or cuckolds. In this group, the body is enveloped in a bony box, made of six-sided scutes connected by sutures, leaving only the jaws, fins and tail free. The spinous dorsal fin is wholly wanting. There are no ventral fins, and the outer fins are short and small. The trunkfishes live in shallow water in the tropical seas. They are slow of motion, though often brightly colored.

Against most of their enemies they are protected by the bony case. The species range from four inches to a foot in length, so far as known. They are not poisonous, and are often baked in the shell. Three genera are recognized: Lactophrys with the carapace, three-angled; Ostracion with four angles; and Aracana, resembling Ostracion, but with the carapace not closed behind the anal fin. In each of these genera there is considerable minor variation due to the presence or absence of spines on the bony shell. In some species, called cuckolds, or cowfishes, long horns are developed over the eye. Others have spines on some other part of the shield and some have no spines at all. No species are found in Europe, and none on the Pacific coast of America. The three-angled species, called Lactophrys, are native chiefly to the West Indies, sometimes carried by currents to Guinea, and one is described from Australia. Lactophrys tricornis of the West Indies has long horns over the eye; Lactophrys trigonus has spines on the lower parts only. Lactophrys triqueter is without spines, and the fourth American species, Lactophrys bicaudalis, is marked by large black spots. The species of Ostracion radiate from the East Indies. One of them, Ostracion gibbosum, has a turret-like spine on the middle of the back, causing the carapace to appear five-angled; Ostracion diaphanum has short horns over the eye, and Ostracion cornutum very long ones; Ostracion immaculatus, the common species of Japan, is without spines; Ostracion sebæ of Hawaii and Samoa is deep, rich blue with spots of golden. Aracana is also of East Indian origin; Aracana aculeata, with numerous species, is common in Japan. A fossil species of Ostracion (O. micrurum) is known from the Eocene of Monte Bolca.

=The Gymnodontes.=—The group of Gymnodontes, having the teeth united in a turtle-like beak, carry still further the degeneration of scales and fins. There is no trace of spinous dorsal, or ventral. The scales are reduced to thorns or prickles, or are lost altogether. All the species have the habit of inflating themselves with air when disturbed, thus floating, belly upward, on the surface of the water. Very few, and these only northern species, are used as food, the flesh of the tropical forms being generally poisonous, and that often in a higher degree than any other fishes whatever.

=The Triodontidæ.=—The most generalized family is that of the Triodontidæ. These fishes approach the Balistidæ in several regards, having the body compressed and covered with rough scales. The teeth form a single plate in the lower jaw, but are divided on the median line above. The compressed, fan-like, ventral flap is greatly distensible. Triodon bursarius, of the East Indies and northward to Japan, is the sole species of the family.

=The Globefishes: Tetraodontidæ.=—In the Tetraodontidæ (globefishes, or puffers), each jaw is divided by a median suture. The dorsal and anal are short, and the ventrals are reduced in number, usually fifteen to twenty (7 + 13 to 7 + 9). The walls of the belly are capable of extraordinary distension, so that when inflated, the fish appears like a globe with a beak and a short tail attached. The principal genus Spheroides contains a great variety of forms, forming a closely intergrading series. In some of these the body is smooth, in others more or less covered with prickles, usually three-rooted. In some the form is elongate, the color silvery, and the side of the belly with a conspicuous fold of skin. In these species, the caudal is lunate and the other fins falcate, and with numerous rays. But these forms (called Lagocephalus) pass by degrees into the short-bodied forms with small rounded fins, and no clear line has yet been drawn separating the group into genera. In these species each nostril has a double opening. Lagocephalus lagocephalus, large and silvery, is found in Europe. Lagocephalus lævigatus replaces it on the Atlantic Coast of North America. In Japan are numerous forms of this type, the venomous Lagocephalus sceleratus being one of the best known. Numerous other Japanese species, Spheroides xanthopterus, rubripes, pardalis, ocellatus, vermiculatus, chrysops, etc., mark the transition to typical Spheroides. Spheroides maculatus is common on our Atlantic coast, the puffer, or swell-toad of the coastwise boys who tease it to cause it to swell. Spheroides spengleri and S. testudineus abound in the West Indies. Spheroides politus on the west coast of Mexico.

In Tetraodon the nasal tentacle is without distinct opening, its tip being merely spongy. The species of this genus are even more inflatable and are often strikingly colored, the young sometimes having the belly marked by concentric stripes of black which disappear with age. Tetraodon hispidus abounds in estuaries and shallow bays from Hawaii to India. In Hawaii, it is regarded as the most poisonous of all fishes (muki-muki) and it is said that its gall was once used to poison arrows. Tetraodon fahaka is a related species, the first known of the family. It is found in the Nile. Tetraodon lacrymatus, black with white spots, is common in Polynesia. Tetraodon aërostaticus, with black spots, is frequently taken in Japan, and Tetraodon setosus is frequent on the west coast of Mexico. This species is subject to peculiar changes of color. Normally dark brown, with paler spots, it is sometimes deep blue, sometimes lemon-yellow and sometimes of mixed shades. Specimens showing these traits were obtained about Clarion Island of the Revillagigedos. No Tetraodon occurs in the West Indies. Colomesus psittacus, a river fish of the northern part of South America, resembles Spheroides, but shows considerable difference in the skull.

But few fossil Tetraodontidæ have been recognized. These are referred to Tetraodon. The earliest is Tetraodon pygmæus from Monte Bolca.

The Chonerhinidæ of the East Indies are globefishes having the dorsal and anal fins very long, the vertebræ more numerous (12 + 17), twenty-nine in number. Chonerhinus naritus inhabits the rivers of Sumatra and Java.

The little family of Tropidichthyidæ is composed of small globefishes, with a sharply-keeled back, and the nostrils almost, or quite, wanting. The teeth are as in the Tetraodontidæ. The skeleton differs considerably from that of Spheroides, apparently justifying their separation as a family. The species are all very small, three to six inches in length, and prettily colored. In the West Indies Tropidichthys rostratus is found. Tropidichthys solandri abounds in the South Seas, dull orange with blue spots. Tropidichthys rivulatus is common in Japan and several ether species are found in Hawaii.

Other species occur on the west coast of Mexico, in Polynesia, and in the East Indies.

=The Porcupine-fishes: Diodontidæ.=—In the remaining families of Gymnodontes, there is no suture in either jaw, the teeth forming an undivided beak. The Diodontidæ, or porcupine-fishes, have the body spherical or squarish, and armed with sharp thorns, the bases of which are so broad as to form a continuous coat of mail. In some of them, part of the spines are movable, these being usually two-rooted; in others, all are immovable and three-rooted. All are reputed poisonous, especially in the equatorial seas.

In Diodon the spines are very long, the anterior ones, at least, movable. The common porcupine-fish, Diodon hystrix, is found in all seas, and often in abundance. It is a sluggish fish, olive and spotted with black. It reaches a length of two feet or more, and by its long spines it is thoroughly protected from all enemies. A second species, equally common, is the lesser porcupine-fish, Diodon holacanthus. In this species, the frontal spines are longer than those behind the pectoral, instead of the reverse, as in Diodon hystrix. Many species of Diodon are recorded from the Eocene, besides numerous species from later deposits. One of these, as Heptadiodon heptadiodon from the Eocene of Italy, with the teeth subdivided, possibly represents a distinct family. Diodon erinaceus is found in the Eocene of Monte Bolca and Progymnodon hilgendorfi in the Eocene of Egypt.

In the rabbit-fishes (Chilomycterus) the body is box-shaped, covered with triangular spines, much shorter and broader at base than those of Diodon. Numerous species are known.

Chilomycterus schœpfi is the common rabbit-fish, or swell-toad of our Atlantic coast, light green, prettily varied with black lines. The larger, Chilomycterus affinis, with the pectoral fin spotted with black, is widely diffused through the Pacific. It is rather common in Japan, where it is the torabuku, or tiger puffer. It is found also in Hawaii, and it is once recorded by Dr. Eigenmann from San Pedro, California, and once by Snodgrass and Heller, from the Galapagos.

=The Head-fishes: Molidæ.=—The headfishes, or Molidæ, also called sunfishes, have the body abbreviated behind so that the dorsal, anal, and caudal fins seem to be attached to the posterior outline of the head. This feature, constituting the so-called gephyrocercal tail is a trait of specialized degradation.

Mola mola, the common head-fish or sunfish, is found occasionally in all tropical and temperate seas. Its form is almost circular, having been compared by Linnæus to a mill-wheel (mola), and its surface is covered with a rough, leathery skin. It swims very lazily at the surface of the water, its high dorsal often rising above the surface. It is rarely used as food, though not known to be poisonous. The largest example known to the writer was taken at Redondo Beach, California, by Mr. Thomas Shooter, of Los Angeles. This specimen was 8 feet 2 inches in length, and weighed 1200 pounds. Another, almost as large, was taken at San Diego, in April, 1904. No difference has been noticed among specimens from California, Cape Cod, Japan, and the Mediterranean. The young, however, differ considerably from the adult, as might be expected in a fish of such great size and extraordinary form. (See Figs. 109 and 110, Vol. I.)

Fragments named Chelonopsis, and doubtfully referred to Mola, are found in the Pliocene of Belgium. Certain jaws of cretaceous age, attributed to Mola, probably belong, according to Woodward, to a turtle.

In the genus Ranzania, the body is more elongate, twice as long as deep, but as in Mola, the body appears as if bitten off and then provided with a fringe of tail. The species are rarely taken. Ranzania truncata is found in the Mediterranean and once at Madeira. Ranzania makua, known as the king of the mackerels about Hawaii, is beautifully colored brown and silvery. This species has been taken once in Japan.

In Hawaii it is believed that all the Scombroid fishes are subject to the rule of the makua and that they will disappear if this fish be killed. By a similar superstition, Regalecus glesne is "king of the herrings" in Norway and about Cape Flattery, Trachypterus rex salmonorum is "king of the salmon."

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XXV. PAREIOPLITÆ, OR MAILED-CHEEK FISHES

=THE Mailed-cheek Fishes.=—The vast group of Pareioplitæ (Loricati) or mailed-cheek fishes is characterized by the presence of a "bony stay" or backward-directed process from the third suborbital. This extends backward across the cheek toward the preopercle. In the most generalized forms this bony stay is small and hidden under the skin. In more specialized forms it grows larger, articulates with the preopercle, and becomes rough or spinous at its surface. Finally, it joins the other bones to form a coat of mail which covers the whole head. In degenerate forms it is again reduced in size, finally becoming insignificant.

The more primitive Pareioplitæ (παρεία, cheek; ὁπλιτής, armed) closely resemble the Percomorphi, having the same fins, the same type of shoulder-girdle, and the same insertion of the ventral fins. In the more specialized forms the ventral fins remain thoracic, but almost all other parts of the anatomy are greatly distorted. In all cases, so far as known to the writer, the hypercoracoid is perforate as in the Percomorphi. There are numerous points of resemblance between the Cirrhitidæ and the Scorpænidæ, and it is probable that the Scorpænidæ with all the other Pareioplitæ sprang from some perciform stock allied to Cirrhitidæ and Latrididæ.

Fossil mailed-cheek fishes are extremely few and throw little light on the origin of the group. Those belong chiefly to the Cottidæ. Lepidocottus, recorded from the Miocene and Oligocene, seems to be the earliest genus.

=The Scorpion-fishes: Scorpænidæ.=—The vast family of Scorpænidæ, or scorpion-fishes, comprises such a variety of forms as almost to defy diagnosis. The more primitive types are percoid in almost all respects, save in the presence of the subocular stay. Their scales are ctenoid and well developed. The dorsal spines are numerous and strong. The ventral fins are complete and normally attached; the anal has three strong spines. The cranium shows only a trace of spiny ridges, and the five spines on the preoperculum are not very different from those seen in some species of bass. The gill-arches are, however, different, there being but 3½ gills and no slit behind the last. Otherwise the mouth and pharanx show no unusual characters. In the extremes of the group, however, great changes take place, the head becomes greatly distorted with ridges and grooves, the anal spines are lost, and the dorsal spines variously modified. The scales may be lost or replaced by warts or prickles and the ventral fins may be greatly reduced. Still the changes are very gradual, and it is not easy to divide the group into smaller families.

The most primitive existing genus is doubtless Sebastes. The familiar rosefish, Sebastes marinus, is found on both shores of the north Atlantic. It is bright red in color and is valued as food. As befits a northern fish, it has an increased number of vertebræ (31) and the dorsal spines number 15. From its large haddock-like eye it has been called the Norway haddock. It is an important food-fish in New England as well as in northern Europe.

In the north Pacific Sebastes gives place to Sebastolobus, with three species (macrochir, altivelis, and alascanus), all bright-red fishes of soft substance and living in rather deep water. Sebastolobus is characterized by its two-lobed pectoral fin, the lower rays being enlarged.

The genus Sebastodes, with its rougher-headed ally Sebastichthys, with 13 dorsal spines and the vertebræ 27, ranges farther south than Sebastes and forms one of the most characteristic features of the fauna of California and Japan, 50 species occurring about California and 25 being already known from Japan. One species (Sebastichthys capensis) is recorded from the Cape of Good Hope, and two, Sebastichthys oculatus and S. darwini, from the coast of Chile.

Within the limits of Sebastodes and Sebastichthys is a very large range of form and color, far more than should exist within the range of a natural genus. On the other hand, all attempts at generic subdivision have failed because the species form a number of almost perfectly continuous series. At one extreme are species with large mouths, small scales, relatively smooth cranium, and long gill-rakers. At the other extreme are robust species, with the head very rough, the mouth moderate, the scales larger, and the gill-rakers short and thick. Still other species have slender cranial spines and spots of bright pink in certain specialized localities. These approach the genus Helicolenus as other species approach Scorpæna.

The various species are known in California as rockfish, or rock-cod, in Japan as Soi and Mebaru. In both regions they form a large part of the bulk of food-fishes, the flesh being rather coarse and of moderate flavor. All the species so far as known are ovoviviparous, the young being brought forth in summer in very great number, born at the length of about ¼ of an inch. The species living close to shore are brown, black, or green. Those living in deeper waters are bright red, and in still deeper waters often creamy or gray, with the lining of the mouth and the peritoneum black. The largest species reach a length of two or three feet, the smallest eight or ten inches. None are found between Lower California and Peru and none south of Nagasaki in Japan. Of the California species the following are of most note: Sebastodes paucispinis, the Bocaccio of the fishermen, from its large mouth, is an elongate fish, dull red in color, and reaching a very large size. In deeper waters are Sebastodes jordani and Sebastodes goodei, the former elongate and red, the latter more robust and of a very bright crimson color. Sebastodes ovalis, the viuva, and Sebastodes entomelas are grayish in hue, and the related Sebastodes proriger is red. The green rockfish Sebastodes flavidus is common along the shore, as also the black rockfish, known as pêche prêtre or priestfish, Sebastodes mystinus. Less common is Sebastodes melanops. Similar to this but more orange in color is the large Sebastodes miniatus. Somewhat rougher-headed is the small grass rockfish, Sebastodes atrovirens. On the large red rockfish, Sebastichthys ruberrimus, the spinous ridges are all large and rough serrate. On the equally large Sebastichthys levis these ridges are smooth. Both these species are bright red in color. Sebastichthys rubrovinctus, called the Spanish-flag, is covered with broad alternating bands of deep crimson and creamy pink. It is the most handsomely colored of our marine fishes and is often taken in southern California. Sebastichthys elongatus is a red species with very large mouth. Several other species small in size are red, with three or four spots of bright pink. The commonest of these is the corsair, Sebastichthys rosaceus, plain red and golden. Another species is the green and red flyfish, Sebastichthys rhodochloris. Sebastichthys constellatus is spotted with pink and Sebastichthys chlorostictus with green. To this group with pink spots the South American and African species belong, but none of the Japanese. Sebastodes aleutianus is a large red species common in Alaska and Sebastodes ciliatus a green one. About the wharves in California and northward the brown species called Sebastichthys auriculatus is abundant. In the remaining species the spinous ridges are progressively higher, though not so sharp as in some of those already named. Sebastichthys maliger has very high dorsal spines and a golden blotch on the back. In Sebastichthys caurinus and especially Sebastichthys vexillaris the spines are very high, but the coloration is different, being reddish brown. Sebastichthys nebulosus is blue-black with golden spots. Sebastichthys chrysomelas is mottled black and yellow. Sebastichthys carnatus is flesh-color and green. Sebastichthys rastrelliger is a small, blackish-green species looking like Sebastodes atrovirens, but with short gill-rakers. Sebastichthys hopkinsi and Sebastichthys gilberti are small species allied to it. The treefish, Sebastichthys serriceps, has very high spines on the head, and the olive body is crowned by broad black bands. Still more striking is the black-banded rockfish, Sebastichthys nigrofasciatus, with very rough head and bright red body with broad cross-bands of black.

Of the Japanese species the commonest, Sebastodes inermis, the Mebaru, much resembles Sebastodes flavidus. Sebastodes fuscescens looks like Sebastodes melanops, as does also Sebastodes taczanowskii. Sebastodes matsubaræ and S. flammeus and S. iracundus, bright-red off-shore species, run close to Sebastodes aleutianus. Sebastichthys pachycephalus suggests Sebastichthys chrysomelas. Sebastodes steindachneri and S. itinus are brighter-colored allies of Sebastodes ovalis and Sebastodes scythropus and Sebastodes joyneri represent Sebastodes proriger. Sebastichthys trivittatus, green, striped with bright golden, bears some resemblance to Sebastichthys maliger. Sebastichthys elegans, Sebastichthys oblongus, and Sebastichthys mitsukurii, dwarf species, profusely spotted, have no analogues among the American forms. Sebastodes glaucus of the Kurile Islands has 14 dorsal spines and is not closely related to any other. Fourteen dorsal spines are occasionally present in Sebastichthys elegans. All the other species show constantly 13.

The genus Sebastiscus has the general appearance of Sebastodes, and like the latter possesses a large air-bladder. It however agrees with Scorpæna in the possession of but 12 dorsal spines and 24 vertebræ. The two known species are common in Japan. Sebastiscus marmoratus, mottled brown, is everywhere abundant along the coast, and the pretty Sebastiscus albofasciatus, pink, violet, and golden, represents it in equal abundance in deeper water.

The genus Sebastopsis differs from Sebastodes only in having no teeth on the palatines. The species, all of small size and red or varied coloration, are confined to the Pacific. Sebastopsis xyris occurs in lower California and Sebastopsis guamensis and S. scaber in Polynesia. Species of this genus are often found dried in Chinese insect boxes.

Helicolenus differs from Sebastiscus only in the total absence of air-bladder. The species are all bright crimson in color, very handsome, and live in deep water. Helicolenus dactylopterus is rather common in the Mediterranean, and is sometimes taken in the Gulf Stream, and also in Japan, where two or three other species occur.

Neosebastes is much like Sebastodes, but the suborbital stay bears strong spines and the dorsal is very high. Neosebastes panda is found in Australia, and N. entaxis in Japan. Setarches is distinguished by the cavernous bones of its head. Species are found in both the Atlantic and Pacific in deep water. Several other peculiar or transitional genera are found in different parts of the Pacific.

In Scorpæna the head is more uneven in outline than in Sebastodes and Sebastichthys, skinny flaps are often present on head and body, the air-bladder is wanting, there are 12 dorsal spines and 24 vertebræ, and on each dorsal spine is a small venom-secreting gland. The species are very numerous, highly varied in color, and found in all warm seas, being known as scorpion-fishes or Rascacios. Two species, Scorpæna scrofa and Scorpæna porcus, are common in the Mediterranean, being regarded as good food-fishes, though disliked by the fishermen.

Of the numerous West Indian species, Scorpæna plumieri, Scorpæna grandicornis, and Scorpæna brasiliensis are best known. Scorpæna guttata is common in southern California and is an excellent food-fish. Scorpæna mystes is found on the west coast of Mexico. Scorpæna onaria and S. izensis are found in Japan. Fossil remains referred to Scorpæna are recorded from the Tertiary rocks.

In the islands of the Pacific are numerous dwarf species less than three inches long, which have been set apart as a separate genus, Sebastapistes. The longest known of these is Sebastapistes strongensis, named from Strong Island, abundant in crevices in the corals throughout Polynesia, and much disliked by fishermen.

The genus Scorpænopsis differs from Scorpæna in the absence of palatine teeth. It is still more fantastic in form and color. Scorpænopsis cirrhosa, Scorpænopsis fimbriata, and other species are widely distributed through the East Indies and Polynesia.

The lion-fishes (Pterois) of the tropical Pacific are remarkable for their long pectoral fins, elongate dorsal spines, and zebra-like coloration. The numerous species are fantastic and handsomely colored, but their poisoned, needle-like spines are dreaded by fishermen. They lurk in crevices in the coral reefs, some of them reaching a foot in length.

Inimicus japonicus, common in Japan, has a depressed and monstrous head and a generally bizarre appearance. It is usually black in color but is largely bright red when found among red algæ. A related species, Inimicus aurantiacus, is blackish when near shore, but lemon-yellow in deep water. (See frontispiece.) A related species in the East Indies is Pelor filamentosum, called Nohu or Gofu in Polynesia.

Still more monstrous are the species of Synanceia, short, thick-set, irregularly formed fishes, in which the poisoned spines reach a high degree of venom. The flesh in all these species is wholesome, and when the dorsal spines are cut off the fishes sell readily in the markets. These fishes lie hidden in cavities of the reefs, being scarcely distinguishable from the rock itself. (See Fig. 168, Vol. I.)

The black Emmydrichthys vulcanus of Tahiti lies in crevices of lava, and could scarcely be distinguished from an irregular lump of lava-rock.

A related form, Erosa erosa, the daruma-okose of Japan, is monstrous in form but often beautifully colored with crimson and gray.

In Congiopus the very strong dorsal spines begin in the head, and the mouth is very small. Dr. Gill makes this genus the type of a distinct family, Congiopodidæ.

Besides these, very many genera and species of small poison-fishes, called okose in Japan, abound in the sandy bays from Tokio to Hindostan and the Red Sea. Some of these are handsomely colored, others are fantastically formed. Paracentropogon rubripinnis and Minous adamsi are the commonest species in Japan. Trachicephalus uranoscopus abounds in the bays of hina. Snyderina yamanokami occurs in Southern Japan.

But few fossil Scorpænidæ are recorded. Scorpænopterus siluridens, a mailed fish from the Vienna Miocene, with a warty head, seems to belong to this group, and Ampheristus toliapicus, with a broad, depressed head, is found in the London Eocene, and various Miocene species have been referred to Scorpæna. Sebastodes rosæ is based on a fragment, probably Pleistocene, from Port Harford, California.

The small family of the Caracanthidæ consists of little fishes of the coral reefs of the Pacific. These are compressed in form, and the skin is rough with small prickles, the head being feebly armed. The species are rare and little known, brown in color with pale spots.

=The Skilfishes: Anoplopomidæ.=—The small family of skilfishes or Anoplopomidæ consists of two species found on the coast of California and northward. These resemble the Scorpænidæ, having the usual form of nostrils, and the suborbital stay well developed. The skull is, however, free from spines, the scales are small and close-set, and the sleek, dark-colored body has suggested resemblance to the mackerel or hake. Anoplopoma fimbria, known as skilfish, beshow, or coalfish, is rather common from Unalaska to Monterey, reaching a length of two feet or more. In the north it becomes very fat and is much valued as food. About San Francisco it is dry and tasteless.

=The Greenlings: Hexagrammidæ.=—The curious family of greenlings, Hexagrammidæ, is confined to the two shores of the North Pacific. The species vary much in form, but agree in the unarmed cranium and in the presence of but a single nostril on each side, the posterior opening being reduced to a minute pore. The vertebræ are numerous, the scales small, and the coloration often brilliant. The species are carnivorous and usually valued as food. They live in the kelp and about rocks in California and Japan and along the shores of Siberia and Alaska. The atka-fish (Pleurogrammus monopterygius) is one of the finest of food-fishes. This species reaches a length of eighteen inches. It is yellow in color, banded with black, and the flesh is white and tender, somewhat like that of the Lake whitefish (Coregonus clupeiformis), and is especially fine when salted. This fish is found about the Aleutian Islands, especially the island of Atka, from which it takes its name. It is commercially known as Atka mackerel.

In this genus there are numerous lateral lines, and the dorsal fin is continuous. In Hexagrammos, the principal genus of the family, the dorsal is divided into two fins, and there are about five lateral lines on each side.

Hexagrammos decagrammus is common on the coast of California, where it is known by the incorrect name of rock-trout. It is a well-known food-fish, reaching a length of eighteen inches. The sexes are quite unlike in color, the males anteriorly with blue spots, the females speckled with red or brown.

Hexagrammos octogrammus, the common greenfish of Alaska, and the greenling Hexagrammos stelleri, are also well-known species. Close to the latter species is the Abura ainame, or fat cod, Hexagrammos otakii, common throughout Japan. The red rock-trout, Hexagrammos superciliosus, is beautifully variegated with red, the color being extremely variable. Other species are found in Japan and Kamchatka. Agrammus agrammus of Japan differs in the possession of but one lateral line. Ophiodon elongatus, the blue cod, cultus cod, or Buffalo cod of California, is a large fish of moderate value as food, much resembling a codfish, but with larger mouth and longer teeth. The flesh and bones are deeply tinged with bluish green. Cultus is the Chinook name for worthless. Zaniolepis latipinnis is a singular-looking fish, very rough, dry, and bony, occasionally taken on the California coast. Oxylebius pictus is a small, handsome, and very active little fish, whitish with black bands, common among rocks and algæ on the California coast. It is, however, rarely brought into the markets, as it shows great skill in escaping the nets.

No fossil Hexagrammidæ are known.

=The Flatheads or Kochi: Platycephalidæ.=—The family of Platycephalidæ consists of spindle-shaped fishes, with flattened, rough heads and the body covered with small, rough scales. About fifty species occur in the East Indian region, where the larger ones are much valued as food. The most abundant species and usually the largest in size is Platycephalus insidiator, the kochi of the Japanese. The genus Insidiator contains smaller species with larger scales. In all these the head is very much depressed, a feature which separates them from all the Scorpænidæ. Hoplichthys langsdorfi, the nezupo or rat-tail of Japan, is the type of a separate family, Hoplichthyidæ, characterized by a bony armature of rough plates. Bembras japonicas, another little Japanese fish, with the ventrals advanced in position and the skin with rough plates, is the type of the family of Bembradidæ.

=The Sculpins: Cottidæ.=—The great family of Cottidæ or sculpins is one especially characteristic of the northern seas, where a great variety of species is found. These differ in general from the Scorpænidæ, from which they are perhaps derived, in the greater number of vertebræ and in the relative feebleness or degeneration of the spinous dorsal, the ventrals, and the scales. In all these regards great variation exists. In the most primitive genus, Jordania, the body is well scaled, the spinous dorsal well developed, and the ventral rays I, 5. In Hemitripterus a large number of dorsal spines remains, but the structure in other regards is highly modified. In the most degraded types, Cottunculus, Psychrolutes, Gilbertidia, which are also among the most specialized, there is little trace of spinous dorsal, the scales are wholly lost, and the ventral fin is incomplete. Most of the species of Cottidæ live on the bottom in shallow seas. Some are found in deep water and a few swarm in the rivers. All are arctic or subarctic, none being found to the south of Italy, Virginia, California, and Japan. None are valued as food, being coarse and tough. Scarcely any are found fossil.

Of the multitude of genera of Cottidæ we notice a few of the most prominent. Jordania zonope, a pretty little fish of Puget Sound, is the most primitive in its characters, being closely allied to the Hexagrammidæ.

Scorpænichthys marmoratus, the great sculpin, or cabezon, of California reaches a length of 2½ feet. It has the ventral rays I, 5, although almost in all the other sculpins the rays are reduced to I, 3 or I, 4. The flesh has the livid blue color seen in the cultus cod Ophiodon elongatus.

To Icelinus, Artedius, Hemilepidotus, Astrolytes, and related genera belong many species with the body partly scaled. These are characteristic of the North Pacific, in which they drop to a considerable depth. Icelus, Triglops, and Artediellus are found also in the North Atlantic, the Arctic fauna of which is derived almost entirely from Pacific sources. The genus Hemilepidotus contains coarse species, with bands of scales. The "Irish lord," Hemilepidotus jordani, a familiar and fantastic inhabitant of Bering Sea, is much valued by the Aleuts as a food-fish, although the flesh is rather tough and without much flavor. Almost equally common in Bering Sea is the red sculpin, Hemilepidotus hemilepidotus, and the still rougher Ceratocottus diceraus. The stone-sculpin, or buffalo-sculpin, Enophrys bison, with bony plates on the side and rough horns on the preopercle, is found about Puget Sound and southward. In all these large rough species from the North Pacific the preopercle is armed with long spines which are erected when the fish is disturbed. This makes it almost impossible for any larger fish to swallow them.

The genera Cottus and Uranidea include the miller's thumbs, also called in America, blob and muffle-jaws, of the Northern rivers. These little fishes are found in Europe, Asia, and America wherever trout are found. They lurk under weeds and stones, moving with the greatest swiftness when disturbed. They are found in every cold stream of the region north of Virginia, and they vie with the sticklebacks in their destruction of the eggs and fry of salmon and trout. Cottus gobio is the commonest species of Europe. Cottus ictalops is the most abundant of the several species of the eastern United States, and Cottus asper in streams of the Pacific Coast, though very many other species exist in each of these regions. The genus Uranidea is found in America. It is composed of smaller species with fewer teeth and fin-rays, the ventrals I, 3. Uranidea gracilis is the commonest of these, the miller's thumb of New England. Rheopresbe fujiyamæ is a large river sculpin in Japan.

Trachidermus ansatus is another river species, the "mountain-witch" (yamanokami) of Japan, remarkable for a scarlet brand on its cheek, conspicuous in life.

The chief genus of Atlantic sculpins is Myoxocephalus, containing large marine species, in structure much like the species of Cottus. Myoxocephalus bubalis is the European fatherlasher, or proach; the European sculpin is Myoxocephalus scorpius. The very similar daddy sculpin of New England is Myoxocephalus grœnlandicus. This species swarms everywhere from Cape Cod northward.

According to Fabricius, Myoxocephalus grœnlandicus is "abundant in all the bays and inlets of Greenland, but prefers a stony coast clothed with seaweed. It approaches the shore in spring and departs in winter. It is very voracious, preying on everything that comes in its way and pursuing incessantly the smaller fish, not sparing the young of its own species, and devouring crustacea and worms. It is very active and bold, but does not come to the surface unless it be led thither in pursuit of other fish. It spawns in December and January and deposits its red-colored roe on the seaweed. It is easily taken with a bait, and constitutes the daily food of the Greenlanders, who are very fond of it. They eat the roe raw."

The little sculpin, or grubby, of the New England coast is Myoxocephalus æneus, and the larger eighteen-spined sculpin is Myoxocephalus octodecimspinosus. Still more numerous and varied are the sculpins of the North Pacific, Myoxocephalus polyacanthocephalus being the best known and most widely diffused. Oncocottus quadricornis is the long-horned sculpin of the Arctic Europe, entering the lakes of Russia and British America. Triglopsis thompsoni of the depths in our own Great Lakes seems to be a dwarfed and degenerate descendant of Oncocottus.

The genus Zesticelus contains small soft-bodied sculpins from the depths of the North Pacific. Zesticelus profundorum was taken in 664 fathoms off Bogoslof Island and Zesticelus bathybius off Japan. In this genus the body is very soft and the skeleton feeble, the result of deep-sea life. Another deep-water genus less degraded is Cottunculus, from which by gradual loss of fins the still more degraded Psychrolutes (paradoxus) and Gilbertidia (sigolutes) are perhaps descended. In sculpins of this type the liparids, or sea-snails, may have had their origin. Among the remaining genera Gymnocanthus (tricuspis, etc.) has no vomerine teeth. Leptocottus (armatus) and Clinocottus (analis) abound on the coast of California, and Pseudoblennius (percoides) is found everywhere along the shores of Japan. Vellitor centropomus of Japan is remarkable among sculpins for its compressed body and long snout. Dialarchus snyderi of the California rock-pools is perhaps the smallest species of sculpin, Blepsias (cirrhosus), Nautichthys (oculofasciatus), and Hemitripterus (americanus), the sea-raven, among the most fantastic. In the last-named genus the spinous dorsal is many-rayed, as in Scorpænidæ, a fact which has led to its separation by Dr. Gill as a distinct family. But the dorsal spines are equally numerous in Jordania, which stands at the opposite extreme of the cottoid series.

In Ascelichthys (rhodorus), a pretty sculpin of the rock-pools of the Oregon region, the ventral fins are wholly lost. Ereunias grallator, a deep-water sculpin from Japan, without ventrals and with free rays below its pectorals, should perhaps represent a distinct family, Ereuniidæ.

The degeneration of the spinous dorsal in Psychrolutes and Gilbertidia of the North Pacific has been already noticed. These genera seem to lead directly from Cottunculus to Liparis.

Fossil Cottidæ are few. Eocottus veronensis, from the Eocene of Monte Bolca, is completely scaled, with the ventral rays I, 5. It is apparently related to Jordania, but is still more primitive. Lepidocottus (aries and numerous other species, mostly from the Miocene) is covered with scales, but apparently has less than five soft rays in the ventrals. Remains of Oncocottus, Icelus, and Cottus are found in Arctic Pleistocene rocks. The family as a whole is evidently of recent date.

The Rhamphocottidæ consist of a single little sculpin with a large bony and singularly formed head, found on the Pacific Coast from Sitka to Monterey. The species is called Rhamphocottus richardsoni.

=The Sea-poachers: Agonidæ.=—The sea-poachers or alligator-fishes, Agonidæ, are sculpins inclosed in a coat of mail made by a series of overlying plates, much like those of the sea-horses or the catfishes of the family Loricariidæ. So far as structure goes, these singular fishes are essentially like the Cottidæ, but with a different and more perfect armature. The many species belong chiefly to the North Pacific, a few in the Atlantic and on the coast of Patagonia. Some are found in considerable depth of water. All are too small to have value as food and some have most fantastic forms. Only a few of the most prominent need be noticed. The largest and most peculiar species is Percis japonicus of the Kurile Islands. Still more fantastic is the Japanese Draciscus sachi with sail-like dorsal and anal. Agonus cataphractus, the sea-poacher, is the only European species. Podothecus acipenserinus, the alligator-fish, is the commonest species of the North Pacific. Pallasina barbata is as slender as a pipefish, with a short beard at the chin. Aspidophoroides monopterygius of the Atlantic and other similar species of the Pacific lack the spinous dorsal fin.

No fossil Agonidæ are known.

=The Lump-suckers: Cyclopteridæ.=—The lump-suckers, Cyclopteridæ, are structurally very similar to the Cottidæ, but of very different habit, the body being clumsy and the movements very slow. The ventral fins are united to form a sucking disk by which these sluggish fishes hold fast to rocks. The skeleton is feebly ossified, the spinous dorsal fin wholly or partly lost, the skin smooth or covered with bony warts. The slender suborbital stay indicates the relation of these fishes with the Cottidæ. The species are chiefly Arctic, the common lumpfish or "cock and hen paddle," Cyclopterus lumpus, abounding on both shores of the North Atlantic. It reaches a length of twenty inches, spawning in eel-grass where the male is left to watch the eggs. Cyclopterichthys ventricosus is a large species with smooth skin from the North Pacific.

=The Sea-snails: Liparididæ.=—The sea-snails, Liparididæ are closely related to the lumpfishes, but the body is more elongate, tadpole shaped, covered with very lax skin, like the "wrinkled skin on scalded milk." In structure the liparids are still more degenerate than the lumpfishes. Even the characteristic ventral disk is lost in some species (Paraliparis; Amitra) and in numerous others the tail is drawn out into a point (leptocercal), a character almost always a result of degradation. The dorsal spines are wanting or imbedded in the loose skin, and all trace of spines on the head is lost, but the characteristic suborbital stay is well developed. The numerous species are all small, three to twelve inches in length. They live in Arctic waters, often descending to great depths, in which case the body is very soft. One genus, Enantioliparis, is found in the Antarctic. In the principal genus, Liparis, the ventral disk is well developed, and the spinous dorsal obsolete. Liparis liparis is found on both shores of the North Atlantic, and is subject to large variations in color. Liparis agassizi is abundant in Japan and northward, and Liparis pulchellus in California. In the most primitive genus, Neoliparis, a notch in the fin indicates the separation of the spinous dorsal. Neoliparis montagui is common in Europe, replaced in New England by Neoliparis atlanticus. Careproctus, with numerous elongate species, inhabits depths of the North Pacific. In Paraliparis (or Hilgendorfia) ulochir, the ventral disk is gone and the lowest stage of degradation of the Loricate or Scorpæna-Cottus type of fishes is reached. No fossil lump-suckers or liparids are recorded, although remains of Cyclopterus lumpus are found in nodules of glacial clay in Canada.

=The Baikal Cods: Comephoridæ.=—The family of Comephoridæ includes Comephorus baikalensis, a large fresh-water fish of Lake Baikal in Siberia, having no near affinities with any other existing fish, but now known to be a mail-cheek fish related to the Cottidæ. The body is elongate, naked, with soft flesh and feeble skeleton. The mouth is large, with small teeth, and the skull has a cavernous structure. There are no ventral fins. The spinous dorsal is short and low, the second dorsal and anal many-rayed, and the pectoral fins are excessively long, almost wing-like; the vertebræ number 8 + 35 = 43, and unlike most fresh-water fishes, the species has no air-bladder. Little is known of the habits of this singular fish. Another genus is recently described under the name of Cottocomephorus.

=Suborder Craniomi: the Gurnards, Triglidæ.=—A remarkable offshoot from the Pareioplitæ is the suborder of gurnards, known as Craniomi (κράνιον, skull; ὤμος, shoulder). In these fishes the suborbital stay is highly developed, much as in the Agonidæ, bony externally and covering the cheeks. The shoulder-girdle is distorted, the post-temporal being solidly united to the cranium, while the postero-temporal is crowded out of place by the side of the proscapula. In other regards these fishes resemble the other mail-cheek forms, their affinities being perhaps closest with the Agonidæ or certain aberrant Cottidæ as Ereunias.

In the true gurnards or Triglidæ the head is rough and bony, the body covered with rough scales and below the pectoral fin are three free rays used as feelers by the fish as it creeps along the bottom. These free rays are used in turning over stones, exploring shells and otherwise searching for food. The numerous species are found in the warm seas. In Europe, the genus Trigla, without palatine teeth and with the lateral line armed, is represented by numerous well-known species. Trigla cuculus is a common form of the Mediterranean. Chelidonichthys, similar to Trigla but larger and less fully armed, is found in Asia as well as in Europe. Several species occur in the Mediterranean. Chelidonichthys kumu is a common species in Japan, a large fish with pectorals of a very brilliant variegated blue, like the wings of certain butterflies.

Lepidotrigla, with larger scales, has many species on the coasts of Europe as well as in China and Japan. Lepidotrigla alata, a red fish with a peculiar bony, forked snout, is common in Japan. The American species of gurnards, having teeth on the palatine, belong to the genus Prionotus. Northward these fishes, known as sea-robins, live along the shores in shallow water. In the tropics they descend to deeper water, assuming a red color. Prionotus carolinus is the commonest species in New England. Prionotus strigatus, the striped sea-robin, and Prionotus tribulus, the rough-headed sea-robin, are common species along the Carolina coast. None have much value as food, being dry and bony. Numerous fossil species referred to Trigla are found in the Miocene. Podopteryx, from the Italian Miocene, with small pectorals and very large ventrals, perhaps belongs also to this family, but its real affinities are unknown.

=The Peristediidæ.=—The Peristediidæ are deep-water sea-robins, much depressed, with flat heads, a bony coat of mail, and two free feelers on the pectoral fin instead of three. The species of Peristedion are occasionally taken with the dredge. Peristedion cataphractum is rather common in Europe. The extinct Peristedion urcianense is described from the Pliocene of Orciano, Tuscany.

=The Flying Gurnards: Cephalacanthidæ.=—The flying gurnards, Cephalacanthidæ, differ in numerous respects and are among the most fantastic inhabitants of the sea. The head is short and bony, the body covered with firm scales, and the very long, wing-like pectoral fin is divided into two parts, the posterior and larger almost as long as the rest of the body. This fin is beautifully colored with blue and brownish red. The first spine of the dorsal fin is free from the others and more or less prolonged. The few species of flying gurnard are much alike, ranging widely in the tropical seas, and having a slight power of flight. The flying robin, or batfish, called in Spanish volador or murcielago, Cephalacanthus volitans, is common on both coasts of the Atlantic, reaching a length of eighteen inches. Cephalacanthus peterseni is found in Japan and Cephalacanthus orientalis in the East Indies, Japan, and Hawaii. The immature fishes have the pectoral fins much shorter than in the adult, and differ in other regards. Cephalacanthus pliocenicus occurs in the Lower Pliocene of Orciano, Tuscany.

Petalopteryx syriacus, an extinct flying gurnard found in the Cretaceous of Mount Lebanon, is an ally of Cephalacanthus. The body is covered with four-angled bony plates, and the first (free) spine of the dorsal is enlarged.

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XXVI. GOBIOIDEI, DISCOCEPHALI, AND TÆNIOSOMI

=SUBORDER Gobioidei, the Gobies: Gobiidæ.=—The great family of Gobiidæ, having no near relations among the spiny-rayed fishes, may be here treated as forming a distinct suborder.

The chief characteristics of the family are the following: The ventral fins are thoracic in position, each having one spine and five soft rays, in some cases reduced to four, but never wanting. The ventral fins are inserted very close together, the inner rays the longest, and in most cases the two fins are completely joined, forming a single roundish fin, which may be used as a sucking-disk in clinging to rocks. The shoulder-girdle is essentially perch-like in form, the cranium is usually depressed, the bones being without serrature. There is no lateral line, the gill-openings are restricted to the sides, and the spinous dorsal is always small, of feeble spines, and is sometimes altogether wanting. There is no bony stay to the preopercle. The small pharyngeals are separate, and the vertebræ usually in normal number, 10 + 14 = 24.

The species are excessively numerous in the tropics and temperate zones, being found in lakes, brooks, swamps, and bays, never far out in the sea, and usually in shallow water. Many of them burrow in the mud between or below tide-marks. Others live in swift waters like the darters, which they much resemble. A few reach a length of a foot or two, but most of the species rarely exceed three inches, and some of them are mature at half an inch.

The largest species, Philypnus dormitor, the guavina de rio, is found in the rivers of Mexico and the West Indies. It reaches a length of nearly two feet and is valued as food. Unlike most of the others, in this species there are teeth on the vomer. Other related forms of the subfamily of Eleotrinæ, having the ventral fins separate, are Eleotris pisonis, a common river-fish everywhere in tropical America; Eleotris fusca, a river-fish abounding from Tahiti and Samoa to Hindostan; Dormitator maculatus, the stout-bodied guavina-mapo of the West Indian regions, with the form of a small carp. Guavina guavina of Cuba is another species of this type, and numerous other species having separate ventrals are found in the East Indies, the West Indies, and in the islands of Polynesia. Some species, as Valenciennesia strigata of the East Indies and Vireosa hanæ of Japan, are very gracefully colored. One genus, Eviota, is composed of numerous species, all minute, less than an inch in length. These abound in the crevices in coral-heads. Eviota epiphanes is found in Hawaii, the others farther south. Hypseleotris guntheri, of the rivers and springs of Polynesia, swims freely in the water, like a minnow, never hugging the bottom as usual among gobies.

Of the typical gobies having the ventrals united we can mention but a few of the myriad forms, different species being abundant alike in fresh and salt waters in all warm regions. In Europe Gobius jozo, Gobius ophiocephalus, and many others are common species. The typical genus Gobius is known by its united ventrals, and by the presence of silken free rays on the upper part of the pectoral fin. Mapo soporator swarms about coral reefs in both Indies. Gobionellus oceanicus, the esmeralda or emerald-fish, is notable for its slender body and the green spot over its tongue. Gobiosoma alepidotum and other species are scaleless. Barbulifer ceuthœcus lives in the cavities of sponges. Coryphopterus similis, a small goby, swarms in almost every brook of Japan. The species of Pterogobius are beautifully colored, banded with white or black, or striped with red or blue. Pterogobius virgo and Pterogobius daimio of Japan are the most attractive species. Species of Cryptocentrus are also very prettily colored.

Of the species burrowing in mud the most interesting is the long-jawed goby, Gillichthys mirabilis. In this species the upper jaw is greatly prolonged, longer than the head, as in Opisthognathus and Neoclinus. In the "American Naturalist" for August, 1877, Mr. W. N. Lockington says of the long-jawed goby:

"I call it the long-jawed goby, as its chief peculiarity consists in its tremendous length of jaw. A garpike has a long jaw, and so has an alligator, and it is not unlikely that the title will call up in the minds of some who read this the idea of a terrible mouth, armed with a bristling row of teeth. This would be a great mistake, for our little fish has no teeth worth bragging about, and does not open his mouth any wider than a well-behaved fish should do. The great difference between his long jaws and those of a garpike is that the latter's project forward, while those of our goby are prolonged backward immensely.

"The long-jawed goby was discovered by Dr. J. G. Cooper in the Bay of San Diego, among seaweed growing on small stones at the wharf, and in such position that it must have been out of the water from three to six hours daily, though kept moist by the seaweed.

"On a recent occasion a single Gillichthys, much larger than any of the original types, was presented by a gentleman who said that the fish, which was new to him, was abundant upon his ranch in Richardson's Bay, in the northern part of the Bay of San Francisco; that the Chinamen dug them up and ate them, and that he had had about eleven specimens cooked, and found them good, tasting, he thought, something like eels. The twelfth specimen he had preserved in alcohol, in the interest of natural science. This gentleman had the opportunity of observing something of the mode of life of these fishes, and informed us that their holes, excavated in the muddy banks of tidal creeks, increase in size as they go downward, so that the lower portion is below the water-level, or at least sufficiently low to be kept wet by the percolation from the surrounding mud.

"When the various specimens now acquired were placed side by side, the difference in the relative length of their jaws was very conspicuous, for while in the smallest it was about one-fifth of the total length, in the largest it exceeded one-third.

"As the fish had now been found in two places in the bay, I thought I would try to find it also, and to this end sallied out one morning, armed with a spade, and commenced prospecting in a marsh at Berkeley, not far from the State University. For a long time I was unsuccessful, as I did not know by what outward signs their habitations could be distinguished, and the extent of mud-bank left bare by the retreating tide was, as compared with my powers of delving, practically limitless.

"At last, toward evening, while digging in the bend of a small creek, in a stratum of soft, bluish mud, and at a depth of about a foot below a small puddle, I found five small fishes, which at first I believed to belong to an undescribed species, so little did they resemble the typical G. mirabilis, but which proved, upon a closer examination, to be the young of that species. There was the depressed, broad head, the funnel-shaped ventral 'disk' formed by the union of the two ventral fins, and the compressed tail of the long-jawed goby, but where were the long jaws? The jaws were, of course, in their usual place, but their prolongations had only just begun to grow along the sides of the head, and were not noticeable unless looked for. A comparison of the various specimens proved conclusively that the strange-looking appendage is developed during the growth of the fish, as will be seen by the following measurements of four individuals:

"In the smallest specimen the maxillary expansion extends beyond the orbit for a distance about equal to that which intervenes between the anterior margin of the orbit and the tip of the snout; in No. 2 it reaches to the posterior margin of the preoperculum; in No. 3 it ends level with the gill-opening; while in the largest individual it passes the origin of the pectoral and ventral fins.

"What can be the use of this long fold of skin and cartilage, which is not attached to the head except where it joins the mouth, and which, from its gradual development and ultimate large dimensions, must certainly serve some useful purpose?

"Do not understand that I mean that every part of a creature is of use to it in its present mode of life, for, as all naturalists know, there are in structural anatomy, just as in social life, cases of survival; remains of organs which were at some former time more developed, parallel in their nature to such survivals in costume as the two buttons on the back of a man's coat, once useful for the attachment of a sword-belt. But in this fish we have no case of survival, but one of unusual development; the family (Gobiidæ) to which it belongs presents no similar case, although its members have somewhat similar habits, and the conviction grows upon us, as we consider the subject, that the long jaws serve some useful purpose in the economy of the creature. In view of the half-terrestrial life led by this fish, I am inclined to suspect that the expansion of the upper jaw may serve for the retention of a small quantity of water, which, slowly trickling downward into the mouth and gills, keeps the latter moist when, from an unusually low tide or a dry season, the waters of its native creek fail, perhaps for several hours, to reach the holes in which the fishes dwell. It may be objected to this view that, were such an appendage necessary or even useful, other species of Gobiidæ, whose habits are similar, would show traces of a similar adaptation. This, however, by no means follows. Nature has many ways of working out the same end; and it must be remembered that every real species, when thoroughly known, differs somewhat in habits from its congeners, or at least from its family friends. To take an illustration from the mammalia. The chimpanzee and the spider-monkey are both quadrumanous and both arboreal, yet the end which is attained in the former by its more perfect hands is reached in the latter by its prehensile tail.

"Why may not the extremely long channel formed by the jaw of this rather abnormal member of the goby family be another mode of provision for the requirements of respiration?"

Of the Asiatic genera, Periophthalmus and Boleophthalmus are especially notable. In these mud-skippers the eyes are raised on a short stalk, the fins are strong, and the animal has the power of skipping along over the wet sands and mud, even skimming with great speed over the surface of the water. It chases its insect prey among rocks, leaves, and weeds, and out of the water is as agile as a lizard. Several species of these mud-skippers are known on the coasts of Asia and Polynesia, Periophthalmus barbarus and Boleophthalmus chinensis being the best known. Awaous crassilabris is the common oopu, or river goby, of the Hawaiian streams, and Lentipes stimpsoni is the mountain oopu, capable of clinging to the rocks in the rush of torrents. Paragobiodon echinocephalus is a short thick-set goby with very large head, found in crevices of coral reefs of Polynesia.

In numerous interesting species the first dorsal fin is wanting or much reduced. The crystal goby, Crystallogobius nilssoni, of Europe is one of this type, with the body translucent. Equally translucent is the little Japanese shiro-uwo, or whitefish, Leucopsarion petersi. Mistichthys luzonius of the Philippine Islands, another diaphanous goby, is said to be the smallest of all vertebrates, being mature at half an inch in length. This minute fish is so very abundant as to become an important article of food in Luzon. The rank of "smallest-known vertebrate" has been claimed in turn for the lancelet (Asymmetron lucayanum), the top minnow, Heterandria formosa, and the dwarf sunfish (Elassoma zonatum). Mistichthys luzonius is smaller than any of these, but the diminutive gobies, called Eviota, found in interstices of coral rocks are equally small, and there are several brilliant but minute forms in the reefs of Samoa. The snake-like Eutæniichthys gilli of Japanese rivers is scarcely larger, though over an inch long. Typhlogobius californiensis, "the blindfish of Point Loma," is a small goby, colorless and blind, found clinging in dark crevices of rock about Point Loma and Dead Man's Island in southern California.

Its eyes are represented by mere rudiments, their loss being evidently associated with the peculiar habit of the species, which clings to the under side of stones in relative darkness, though in very shallow water. The flesh is also colorless, the animal appearing pink in life.

In the Japanese species Luciogobus guttatus, common under stones and along the coast, the spinous dorsal, weak in numerous other species, finally vanishes altogether. Other gobies are band-shaped or eel-shaped, the dorsal spines being continuous with the soft rays. Among these are the barreto of Cuba, Gobioides broussoneti, and in Japan Tænioides lacepedei and Trypauchen wakæ, the latter species remarkable for its strong canines. Fossil gobies are practically unknown. A few fragments, otoliths, and partial skeletons in southern Europe have been referred to Gobius, but no other genus is represented.

The family of Oxudercidæ contains one species, Oxuderces dentatus, a small goby-like fish from China. It is an elongate fish, without ventral fins, and with very short dorsal and anal.

=Suborder Discocephali, the Shark-suckers: Echeneididæ.=—Next to the gobies, for want of a better place, we may mention the singular group of Discocephali (δίσκος, disk; κεφαλή, head). In this group the first dorsal fin is transformed into a peculiar laminated sucking-disk, which covers the whole top of the head and the nape. In other respects the structure does not diverge very widely from the percoid type, there being a remarkable resemblance in external characters to the Scombroid genus Rachycentron. But the skeleton shows no special affinity to Rachycentron or to any perciform fish. The basis of the cranium is simple, and in the depression of the head with associated modifications the Discocephali approach the gobies and blennies rather than the mackerel-like forms.

The Discocephali comprise the single family of shark-suckers or remoras, the Echeneididæ. All the species of this group are pelagic fishes, widely diffused in the warm seas. All cling by their cephalic disks to sharks, barracudas, and other free-swimming fishes, and are carried about the seas by these. They do not harm the shark except by slightly impeding its movement. They are carnivorous fishes, feeding on sardines, young herring, and the like. When a shark, taken on the hook, is drawn out of the water the sucking-fish leaves it instantly, and is capable of much speed in swimming on its own account. These fishes are all dusky in color, the belly as dark as the back, so as to form little contrast to the color of the shark.

The commonest species, Leptecheneis naucrates, called pegapega or pegador in Cuba, reaches a length of about two feet and is almost cosmopolitan in its range, being found exclusively on the larger sharks, notably on Carcharias lamia. It has 20 to 22 plates in its disk, and the sides are marked by a dusky lateral band.

Almost equally widely distributed is the smaller remora, or shark-sucker (Echeneis remora), with a stouter body and about 18 plates in the cephalic disk. This species is found in Europe, on the coast of New York, in the West Indies, in California, and in Japan, but is nowhere abundant. Another widely distributed species is Remorina albescens with 13 plates in its disk. Remoropsis brachyptera, with 15 plates and a long soft dorsal, is also occasionally taken. Rhombochirus osteochir is a rare species of the Atlantic with 18 plates, having the pectoral rays all enlarged and stiff. The louse-fish (Phtheirichthys lineatus) is a small and slender remora having but 10 plates in its disk. It is found attached, not to sharks, but to barracudas and spearfishes.

A fossil remora is described from the Oligocene shales in Glarus, Switzerland, under the name of Opisthomyzon glaronensis. It is characterized by the small disk posteriorly inserted. Its vertebræ are 10 + 13 = 24 only. Dr. Storms gives the following account of this species:

"A careful comparison of the proportion of all the parts of the skeleton of the fossil Echeneis with those of the living forms, such as Echeneis naucrates or Echeneis remora, shows that the fossil differs nearly equally from both, and that it was a more normally shaped fish than either of these forms. The head was narrower and less flattened, the preoperculum wider, but its two jaws had nearly the same length. The ribs, as also the neural and hæmal spines, were longer, the tail more forked, and the soft dorsal fin much longer. In fact it was a more compressed type, probably a far better swimmer than its living congeners, as might be expected if the smallness of the adhesive disk is taken into account."

Concerning the relations of the Discocephali Dr. Gill has the following pertinent remarks:

"The family of Scomberoides was constituted by Cuvier for certain forms of known organization, among which were fishes evidently related to Caranx, but which had free dorsal spines. Dr. Günther conceived the idea of disintegrating this family because, inter alias, the typical Scomberoides (family Scombridæ) have more than 24 vertebræ and others (family Carangidæ) had just 24. The assumption of Cuvier as to the relationship of Elacate (Rachycentron) was repeated, but inasmuch as it had 'more than 24 vertebræ' (it had 25 = 12 + 13) it was severed from the free-spined Carangidæ and associated with the Scombridæ. Elacate has an elongated body, flattened head, and a longitudinal lateral band; therefore Echeneis was considered to be next allied to Elacate and to belong to the same family. The very numerous differences in structure between the two were entirely ignored, and the reference of the Echeneis to the Scombridæ is simply due to assumption piled on assumption. The collocation need not, therefore, longer detain us. The possession by Echeneis of the anterior oval cephalic disk in place of a spinous dorsal fin would alone necessitate the isolation of the genus as a peculiar family. But that difference is associated with almost innumerable other peculiarities of the skeleton and other parts, and in a logical system it must be removed far from the Scombridæ, and probably be endowed with subordinal distinction. In all essential respects it departs greatly from the type of structure manifested in the Scombridæ and rather approximates—but very distantly—the Gobioidea and Blennioidea. In those types we have in some a tendency to flattening of the head, of anterior development of the dorsal fin, a simple basis cranii, etc. Nevertheless there is no close affinity, nor even tendency to the extreme modification of the spinous dorsal exhibited by Echeneis. In view of all these facts Echeneis, with its subdivisions, may be regarded as constituting not only a family but a suborder.... Who can consistently object to the proposition to segregate the Echeneididæ as a suborder of teleocephalous fishes? Not those who consider that the development of three or four inarticulate rays (or even less) in the front of the dorsal fin is sufficient to ordinarily differentiate a given form from another with only one or two such. Certainly the difference between the constituents of a disk and any rays or spines is much greater than the mere development or atrophy of articulations. Not those who consider that the manner of depression of spines, whether directly over the following, or to the right or left alternately, are of cardinal importance; for such differences, again, are manifestly of less morphological significance than the factors of a suctorial disk. Nevertheless there are doubtless many who will passively resist the proposition because of a conservative spirit, and who will vaguely refer to the development of the disk as being a 'teleological modification,' and as if it were not an actual fact and a development correlated with radical modifications of all parts of the skeleton at least. But whatever may be the closest relations of Echeneis, or the systematic value of its peculiarities, it is certain that it is not allied to Elacate any more than to hosts of scombroid, percoid, and kindred fishes, and that it differs in toto from it notwithstanding the claims that have been made otherwise. It is true that there is a striking resemblance, especially between the young—almost as great, for example, as that between the placental mouse and the marsupial Antechinomys—but the likeness is entirely superficial, and the scientific ichthyologist should be no more misled than would be the scientific therologist by the likeness of the marsupial and placental mammals."

=Suborder Tæniosomi, the Ribbon-fishes.=—The suborder Tæniosomi (ταινία, ribbon; σῶμα, body), or ribbon-fishes, is made up of strange inhabitants of the open seas, perhaps aberrant derivatives of the mackerel stock. The body is greatly elongate, much compressed, extremely fragile, covered with shining silvery skin. The ribbon-fishes live in the open sea, probably at no very great depth, but are almost never taken by collectors except when thrown on shore in storms or when attacked by other fishes and dragged above or below their depth. When found they are usually reported as sea-serpents, and although perfectly harmless, they are usually at once destroyed by their ignorant captors. The whole body is exceedingly fragile; the bones are porous, thin, and light, containing scarcely any calcareous matter. In the Tæniosomi the ventral fins are thoracic, formed of one or a few soft rays. More remarkable is the character of the caudal fin, which is always distorted and usually not in line with the rest of the body. The teeth are small. The general structure is not very different from that of the cutlass-fishes, Trichiuridæ, and other degraded offshoots from the scombroid group. The species are few and, from the nature of things, very imperfectly known. Scarcely any specimens are perfectly preserved. When dried the body almost disappears, both flesh and bones being composed chiefly of water.

=The Oarfishes: Regalecidæ.=—The Regalecidæ, or oarfishes, have the caudal fin obsolete and the ventrals reduced to long filaments, thickened at the tip. The species reach a length of twenty or thirty feet, and from their great size, slender forms, and sinuous motion have been almost everywhere regarded as sea-serpents. The very long anterior spines of the dorsal fin are tipped with red, and the fish is often and not untruthfully described as a sea-serpent "having a horse's head with a flaming red mane."

The great oarfish, Regalecus glesne (see Fig. 237, Vol. I) was long known to the common people of Norway as king of the herrings, it being thought that to harm it would be to drive the herring to some other coast. The name "king of the herrings" went into science as Regalecus, from rex, king, and halec, herring. The Japanese fancy, which runs in a different line, calls the creature "Dugunonuatatori," which means the "cock of the palace under the sea."

The Atlantic oarfish is named Regalecus glesne, from the Norwegian farm of Glesnæs, where the first recorded specimen, described by Ascanius, was taken 130 years ago. Since then the species has been many times found on the shores of Great Britain and Norway, and once at Bermuda.

In this species the body is half-transparent, almost jelly-like, light blue in color, with some darker cross-stripes, and the head has a long jaw and a high forehead, suggesting the head of a horse. The dorsal fin begins on the head, and the first few spines are very long, each having a red tuft on the end. When the animal is alive these spines stand up like a red mane.

The creature is harmless, weak in muscle as well as feeble in mind. It lives in the deep seas, all over the world. After great storms it sometimes comes ashore. Perhaps this is because for some reason it has risen above its depth and so lost control of itself. When a deep-water fish rises to the surface the change of pressure greatly affects it. Reduction of pressure bursts its blood-vessels, its swim-bladder swells, if it has one, and turns its stomach inside out. If a deep-water fish gets above its depth it is lost, just as surely as a surface fish is when it gets sunk to the depth of half a mile.

Sometimes, again, these deep-sea fishes rush to the shore to escape from parasites, crustaceans that torture their soft flesh, or sharks that would tear it.

Numerous specimens have been found in the Pacific, and to these several names have been given, but the species are not at all clearly made out. The oldest name is that of Regalecus russelli, for the naturalist Patrick Russell, who took a specimen at Vizagapatam in 1788. I have seen two large examples of Regalecus in the museum at Tokio, and several young ones have recently been stranded on the Island of Santa Catalina in southern California. A specimen twenty-two feet long lately came ashore at Newport in Orange County, California. The story of its capture is thus told by Mr. Horatio J. Forgy, of Santa Ana, California:

"On the 22d of February, 1901, a Mexican Indian reported at Newport Beach that about one mile up the coast he had landed a sea-serpent, and as proof showed four tentacles and a strip of flesh about six feet long. A crowd went up to see it, and they said it was about twenty feet long and like a fish in some respects and like a snake in others. Mr. Remsberg and I, on the following day, went up to see it, and in a short time we gathered a crowd and with the assistance of Mr. Peabody prepared the fish and took the picture you have received.

"It measured twenty-one feet and some inches in length, and weighed about 500 or 600 pounds.

"The Indian, when he reported his discovery, said it was alive and in the shallow water, and that he had landed it himself.

"This I very much doubt, but when it was first landed it was in a fine state of preservation and could have easily been shipped to you, but he had cut it to such an extent that shipment or preservation seemed out of the question when we first saw it.

"At the time it came ashore an unusual number of peculiar fishes and sharks were found. Among others, I found a small oarfish about three feet long in a bad state of preservation in a piece of kelp. One side of it was nearly torn off and the other side was decayed."

Mr. C. F. Holder gives this account of the capture of oarfishes in southern California:

"From a zoological point of view the island of Santa Catalina, which lies eighteen miles off the coast of Los Angeles County, southern California, is very interesting, many rare animals being found there. Every winter the dwellers of the island find numbers of argonaut-shells, and several living specimens have been secured, one for a time living in the aquarium which is maintained here for the benefit of students and the entertainment of visitors. A number of rare and interesting fishes wander inshore from time to time. Several years ago I found various Scopeloid fishes, which up to that time had been considered rare, and during the past few years I have seen one oarfish (Regalecus russelli) alive, while another was brought to me dead. From reports I judge that a number of these very rare fishes have been observed here. The first was of small size, not over two feet in length, and was discovered swimming in shallow water along the beach of Avalon Bay. I had an opportunity to observe the radiant creature before it died. Its 'topknot'—it can be compared to nothing else—was a vivid red or scarlet mass of seeming plumes—the dorsal fins, which merged into a long dorsal fin, extending to the tail. The color of the body was a brilliant silver sheen splashed with equally vivid black zebra-like stripes, which gave the fish a most striking appearance.

"The fish was a fragile and delicate creature, a very ghost of a fish, which swam along where the water gently lapped the sands with an undulatory motion, looking like one of its names—the ribbon-fish. The fortunate finder of this specimen could not be persuaded to give it up or sell it, and it was its fate to be pasted upon a piece of board, dried in the sun as a 'curio,' where, as if in retaliation at the desecration of so rare a specimen, it soon disappeared.

"This apparently was the first oarfish ever seen in the United States, so at least Dr. G. Brown Goode wrote me at the time that it had not been reported. In 1899 another oarfish was brought to me, evidently having been washed in after a storm and found within a few yards of the former at Avalon. The discoverer of this specimen also refused to allow it to be properly preserved, or to donate or sell it to any one who would have sent it to some museum, but, believing it valuable as a 'curio,' also impaled it, the delicate creature evaporating under the strong heat of the semitropic sun.

"This, as stated, was the second fish discovered, and during the past winter (1900) a fine large specimen came in at Newport Beach, being reported by H. J. Forgy, of Santa Ana. The newspapers announced that a Mexican had found a young sea-serpent at Newport, and investigation showed that, as in hundreds of similar instances, the man had found a valuable prize without being aware of it. According to the account, the discoverer first saw the fish alive in the surf and hauled it ashore. Being ignorant of its value, he cut it up, bringing in a part of the scarlet fins and a slice of the flesh. This he showed to some men, and led the way to where lay the mutilated remains of one of the finest oar-or ribbon-fishes ever seen. The specimen was twenty-one feet in length, and its weight estimated at five hundred pounds. The finder had so mutilated it that the fish was ruined for almost any purpose. If he had packed it in salt, the specimen would have returned him the equivalent of several months' labor. Apparently the man had cut it up in wanton amusement.

"This recalls a similar incident. I was on one occasion excavating at San Clemente Island, and had remarked that it was a singular fact that all the fine stone ollas were broken. 'Nothing strange about that,' said a half-breed, one of the party. 'I used to herd sheep here, and we smashed mortars and ollas to pass away time.'"

=The Dealfishes: Trachypteridæ.=—The family of Trachypteridæ comprises the dealfishes, creatures of fantastic form and silvery coloration, smaller than the oarfishes and more common, but of similar habit.

Just as in Norway the fantastic oarfish was believed to be the king of the herrings and cherished as such, so among the Indians of Puget Sound another freak fish is held sacred as the king of the salmon. The people about Cape Flattery believe that if one does any harm to this fish the salmon will at once leave the shores. This fable led the naturalists who first discovered this fish to give it its name of Trachypterus rex-salmonorum.

In Europe a similar species (Trachypterus atlanticus) has long been known by the name of dealfish, or vogmar, neither of these names having any evident propriety.

The dealfish is one of the most singular of all the strange creatures of the sea. It reaches a length of three or four feet. Its body is thin as a knife and would be transparent were it not covered over with a shining white pigment which gives to the animal the luster of burnished silver. On this white surface is a large black blotch or two, but no other colors. The head is something like that of the oarfish, to which animal the dealfish bears a close relationship. Both have small teeth and neither could bite if it would, and neither wants to, for they are creatures of the most inoffensive sort. On the head of the dealfish, where the oarfish has its mane, is a long, streamer-like fin. At the end of the tail, instead of the ordinary caudal fin, is a long, slim fin which projects directly upwards at right angles to the direction of the back-bone. No other fish shows this strange peculiarity.

The dealfish swims in the open sea close to the surface of the water. It does not often come near shore, but it is occasionally blown on the beach by storms. Trachypterus rex-salmonorum has been recorded two or three times from Puget Sound and twice from California. The finest specimen known, the one from which our figure is taken, was secured off the Farallones in 1895 by a fisherman named W. C. Knox, and by him sent to Stanford University. The specimen is perfect in all its parts, a condition rare with these fragile creatures, and its picture gives a good idea of the mysterious king of the salmon.

Four of these fishes have been obtained on the coast of Japan, and have been described and figured by the present writer in the annals of the Imperial University of Tokyo. These are different from the California species and are named Trachypterus ishikawæ, but they show the same bright silver color and the same streamers on the head and tail. Probably they, too, in Japan are kings of something or other, or perhaps silver swans from the submarine palace, for along such lines the Japanese fancy is more likely to run.

The young of the dealfish has the caudal symmetrical, and the dorsal spines and ventral rays produced in very long streamers.

According to Goode and Bean, the dealfishes are "true deep-sea fishes, which live at very great depths, and are only found when floating dead on the surface or washed ashore by the waves. Almost nothing is known of their habits except through Nilsson's observations in the far north. This naturalist, as well as Olafson, appears to have had the opportunity of observing them in life. They say that they approach the shore at flood-tide on sandy, shelving bottoms, and are often left by the retreating waves. Nilsson's opinion is that its habits resemble those of the flatfishes, and that they move with one side turned obliquely upward, the other toward the ground; and he says that they have been seen on the bottom in two or three fathoms of water, where the fishermen hook them up with the implements employed to raise dead seals, and that they are slow swimmers. This is not necessarily the case, however, for the removal of pressure and the rough treatment by which they were probably washed ashore would be demoralizing, to say the least. Trichiurus, a fish similar in form, is a very strong, swift swimmer, and so is Regalecus. Whether or not the habits of Trachypterus arcticus, on which these observations were made, are a safe guide in regard to the other forms is a matter of some doubt, but it is certain that they live far from the surface, except near the Arctic Circle, and that they only come ashore accidentally. They have never been taken by the deep-sea dredge or trawl-net, and indeed perfect specimens are very rare, the bodies being very soft and brittle, the bones and fin-rays exceedingly fragile. A considerable number of species have been described, but in most instances each was based on one or two specimens. It is probable that future studies may be as fruitful as that of Emery, who, by means of a series of twenty-three specimens, succeeded in uniting at least three of the Mediterranean species which for half a century or more had been regarded as distinct. The common species of the eastern Atlantic, Trachypterus atlanticus, is not rare, one or more specimens, according to Günther, being secured along the coast of northern Europe after almost every severe gale. We desire to quote the recommendation of Dr. Günther, and to strongly urge upon any one who may be so fortunate as to secure one of these fishes that no attempt should be made to keep it entire, but that it should be cut into short lengths and preserved in the strongest spirits, each piece wrapped separately in muslin."

The family of Stylephoridæ is known from a single specimen of the species, Stylephorus chordatus, taken off Cuba in 1790. In this form the tail ends in a long, whip-like appendage, twice as long as the head.

No fossil dealfishes or oarfishes are known.

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XXVII. SUBORDER HETEROSOMATA

=THE Flatfishes.=—Perhaps the most remarkable offshoot from the order of spiny-rayed fishes is the great group of flounders and soles, called by Bonaparte Heterosomata (ἔτερός, differing; σῶμα, body). The essential character of this group is found in the twisting of the anterior part of the cranium, an arrangement which brings both eyes on the same side of the head. This is accompanied by a great compression of the body, as a result of which the flounders swim horizontally or lie flat on the sand. On the side which is uppermost both eyes are placed, this side being colored, brown or gray or mottled. The lower side is usually plain white. In certain genera the right side is uppermost, in others the left. In a very few, confined to the coast of California, the eyes are on the right or left side indifferently.

The process of the twisting of the head has been already described (see p. 174, Vol. I). The very young have the body translucent and symmetrical, standing upright in the water. Soon the tendency to rest on the bottom sets in, the body leans to left or right, and the lower eye gradually traverses the front of the head to the other side. This movement is best seen in the species of Platophrys, in which the final arrangement of the eyes is a highly specialized one.

In some or all of the soles it is perhaps true that the eye turns over and pierces the cranium instead of passing across it. This opinion needs verification, and the process should be studied in detail in as many species as possible. The present writer has seen it in species of Platophrys only, the same genus in which it was carefully studied by Dr. Carlo F. Emery of Bologna. In the halibut, and in the more primitive flounders generally, the process takes place at an earlier stage than in Platophrys.

=Optic Nerves of Flounders.=—In the Bulletin of the Museum of Comparative Zoology (Vol. XL, No. 5) Professor George H. Parker discusses the relations of the optic nerves in the group of flounders or flatfishes.

In the bony fishes the optic nerves pass to the optic lobes of the brain, the one passing to the lobes of the opposite side simply lying over the other, without intermingling of fibers, such as takes place in the higher vertebrates and in the more primitive fishes.

According to Parker's observations, in ordinary bony fishes the right nerve may be indifferently above or below the other. In 1000 specimens of ten common species, 486 have the left nerve uppermost and 514 the right nerve. In most individual species the numbers are practically equal. Thus, in the haddock, 48 have the left nerve uppermost and 52 the right nerve.

In the unsymmetrical teleosts or flounders, and soles, this condition no longer obtains. In those species of flounder with the eyes on the right side 236 individuals, representing sixteen species, had the left nerve uppermost in all cases.

Of flounders with the eyes on the left side, 131 individuals, representing nine species, all have the right nerve uppermost.

There are a few species of flounders in which reversed examples are so common that the species may be described as having the eyes on the right or left side indifferently. In all these species, however, whether dextral or sinistral, the relation of the nerves conforms to the type and is not influenced by the individual deviation. Thus the starry flounder (Platichthys) belongs to the dextral group. In 50 normal specimens, the eyes on the right have the left nerve dorsal, while the left nerve is also uppermost in 50 reversed examples with eyes on the left. In 15 examples of the California bastard halibut (Paralichthys californicus), normally sinistral, the right eye is always uppermost. It is uppermost in 11 reversed examples.

Among the soles this uniformity or monomorphism no longer obtains. In 49 individuals of four species of dextral soles, the left nerve is uppermost in 24, the right nerve in 25. Among sinistral soles, or tongue-fishes, in 18 individuals of two species, the left nerve is uppermost in 13, the right nerve in 5.

Professor Parker concludes from this evidence that soles are not degenerate flounders, but rather descended from primitive flounders which still retain the dimorphic condition as to the position of the optic nerves, a condition prevalent in all bony fishes except the flounders.

The lack of symmetry among the flounders lies, therefore, deeper than the matter of the migration of the eye. The asymmetry of the mouth is an independent trait, but, like the migration of the eye, is an adaptation to swimming on the side. Each of the various traits of asymmetry may appear independently of the others.

The development of the monomorphic arrangement in flounders Professor Parker thinks can be accounted for by the principle of natural selection. In a side-swimming fish the fixity of this trait has a mechanical advantage. The unmetamorphosed young of the flounder are not strictly symmetrical, for they possess the monomorphic position of the optic nerve. The reversed examples of various species of flounders (these, by the way, chiefly confined to the California fauna) afford "striking examples of discontinuous variation."

A very curious feature among the flounders is the possession in nine of the California-Alaskan species of an accessory half-lateral line. This is found in two different groups, while near relatives in other waters lack the character. One species in Japan has this trait, which is not found in any Atlantic species, or in any other flounders outside the fauna of northern California, Oregon, and Alaska.

=Ancestry of Flounders.=—The ancestry of the flounders is wholly uncertain. Because, like the codfishes, the flounders lack all fin-spines, they have been placed by some authors after the Anacanthini, or codfishes, and a common descent has been assumed. Some writers declare that the flounder is only a codfish with distorted cranium.

A little study of the osteology of the flounder shows that this supposition is without foundation. The flounders have thoracic ventrals, not jugular as in the cod. The tail is homocercal, ending in a large hypural plate, never isocercal, except in degraded soles, in which it is rather leptocercal. The shoulder-girdle, with its perforate hypercoracoid, has the normal perch-like form. The ventral fins have about six rays, as in the perch, although the first ray is never spinous. Pseudobranchiæ are developed, these structures being obsolete in the codfishes. The gills and pharyngeals are essentially as in the perch.

It is fairly certain that the Heterosomata have diverged from the early spiny-rayed forms, Zeoidei, Berycoidei, or Scombroidei of the Jurassic or Cretaceous, and that their origin is prior to the development of the great perch stock.

If one were to guess at the nearest relationships of the group, it would be to regard them as allies of the deep-bodied mackerel-like forms, as the Stromateidæ, or perhaps with extinct Berycoid forms, as Platycormus, having the ventral fins wider than in the mackerel. Still more plausible is the recent suggestion of Dr. Boulenger that the extinct genus Amphistium resembles the primitive flounder. But there is little direct proof of such relation, and the resemblance of larval flounders to the ribbon-fishes may have equal significance. But the ribbon-fishes themselves may be degenerate Scombroids. In any case both ribbon-fishes and flounders find their nearest living relatives among the Berycoidei or Zeoidei, and have no affinity whatever with the isocercal codfish or with other members of the group called Anacanthini.

The Heterosomata are found in all seas, always close to the bottom and swimming with a swift, undulatory motion. They are usually placed in a single family, but the degraded types known as soles may be regarded as forming a second family.

=The Flounders: Pleuronectidæ.=—In the flounders, or Pleuronectidæ, the membrane-bones of the head are distinct, the eyes large and well separated, the mouth not greatly contracted, and the jaws always provided with teeth. Among the 500 species of flounders is found the greatest variation in size, ranging in weight from an ounce to 500 pounds. The species found in arctic regions are most degenerate and these have the largest number of vertebræ and of fin-rays. The halibut has 50 vertebræ (16 + 34), the craig-flounder 58, while in Etropus and other tropical forms the number is but 34 (10 + 24). The common flounders of intermediate geographical range (Paralichthys dentatus, etc.) show intermediate numbers as 40 (10 + 30). The apparent significance of this peculiar series of fact is given on page 212, Vol. I. It is, perhaps, related to the greater pressure of natural selection in the tropics, showing itself in the better differentiation of the bones and consequently smaller number of the vertebræ.

Fossil flounders are very few and give no clue as to the origin of the group. In the Eocene and Miocene are remains which have been referred to Bothus (Rhombus). Bothus minimus is the oldest species known, described by Agassiz from the Eocene of Monte Bolca. In the Miocene are numerous other species of Bothus, as also tubercles referable to Scophthalmus.

On the testimony of fossils alone the genus Bothus, or one of its allies, would be the most primitive of the group. If it be so, the simpler structure of the halibut and its relatives is due to degeneration, which is probable, although their structure has the suggestion of primitive simplicity, especially in the greater approach to symmetry in the head and the symmetry in the insertion of the ventral fins.

Soles have been found in the later Tertiary rocks. Solea kirchbergiana of the Miocene is not very different from species now extant in southern Europe. No remains referable to allies of the halibut or plaice are found in Tertiary rocks, and these relatively simple types must be regarded as of recent origin.

=The Turbot Tribe: Bothinæ.=—The turbot tribe have the mouth large, the eyes and color on the left side, and the ventral fins unlike, that of the left side being extended along the ridge of the abdomen. The species are found in the warm seas only. They are deeper in body than the halibut and plaice, and some of them are the smallest of all flounders. It is probable that these approach most nearly of existing flounders to the original ancestors of the group.

Perhaps the most primitive genus is Bothus, species of which genus are found in Italian Miocene. The European brill, Bothus rhombus, is a common fish of southern Europe, deep-bodied and covered with smooth scales.

Very similar but much smaller in size is the half translucent speckled flounder of our Atlantic coast (Lophopsetta maculata), popularly known as window-pane. This species is too small to have much value as food. Another species, similar to the brill in technical characters but very different in appearance, is the turbot, Scophthalmus maximus, of Europe. This large flounder has a very broad body, scaleless but covered with warty tubercles. It reaches a weight of seventy pounds and has a high value as a food-fish. There is but one species of turbot and it is found in Europe only, on sandy bottoms from Norway to Italy. In a turbot of twenty-three pounds weight Buckland found a roe of five pounds nine ounces, with 14,311,260 eggs. The young retains its symmetrical condition for a relatively long period. No true turbot is found in America and none in the Pacific. Other European flounders allied to the turbot and brill are Zeugopterus punctatus; the European whiff, Lepidorhombus whiff-jagonis; the topknot, Phrynorhombus regius; the lantern-flounder, Arnoglossus laterna, and the tongue-fish, Eucitharus linguatula, the last two of small size and feeble flesh.

In the wide-eyed or peacock flounders, Platophrys podas in Europe, Platophrys lunatus, etc., in America, Platophrys mancus in Polynesia, the eyes in the old males are very far apart, and the changes due to age and sex are greater than in any other genera. The species of this group are highly variegated and lie on the sand in the tropical seas. Numerous small species allied to these abound in the West Indies, known in a general way as whiffs. The most widely distributed of these are Citharichthys spilopterus of the West Indies, Citharichthys gilberti and Azevia panamensis of Panama, Orthopsetta sordida of California, and especially the common small-mouthed Etropus crossotus found throughout tropical America. Numerous other genera and species of the turbot tribe are found on the coasts of tropical Asia and Africa, most of them of small size and weak structure.

Samaris cristatus of Asia is the type of another tribe of flounders and the peculiar hook-jawed Oncopterus darwini of Patagonia represents still another tribe.

=The Halibut Tribe: Hippoglossinæ.=—In the great halibut tribe the mouth is large and the ventral fins symmetrical. The arctic and subarctic species have the eyes and color on the right. Those of the warmer regions (bastard halibut) have the eyes and color on the left. These grow progressively smaller in size to the southward, the mouth being smaller and more feebly armed in southern species.

The largest of the family, and the one commercially of far greatest importance, is the halibut (Hippoglossus hippoglossus). This species is found on both shores of both oceans, north of about the latitude of Paris, Boston, Cape Mendocino, and Matsushima Bay in Japan. Its preference is for off-shore banks of no great depth, and in very many localities it exists in great abundance, reaching a length of 6 to 8 feet and a weight of 600 pounds. It sometimes ranges well out to sea and enters deeper waters than the cod. The flesh is firm, white, and of good quality, although none of the flatfishes have much flavor, the muscles being mostly destitute of oil. Small halibut, called "chicken halibut," are highly esteemed.

Dr. Goode states that the "history of the halibut fishery has been a peculiar one. At the beginning of the present century these fishes were exceedingly abundant on George's Banks; since 1850 they have partially disappeared from this region, and the fishermen have since been following them to other banks, and since 1874 out into deeper and deeper water, and the fisheries are now carried on almost exclusively in the gullies between the off-shore banks and on the outer edges of the banks, in water 100 to 350 fathoms in depth.

"The halibut with its large mouth is naturally a voracious fish, and probably would disdain few objects in the way of fresh meat it would come across. It is said, however, to feed more especially upon crabs and mollusks in addition to fish. These fish 'they waylay lying upon the bottom, invisible by reason of their flat bodies, colored to correspond to the general color of the sand or mud upon which they rest. When in pursuit of their prey they are active and often come quite to the surface, especially when in summer they follow the capelin to the shoal water near the land. They feed upon skates, cod, haddock, menhaden, mackerel, herring, lobsters, flounders, sculpins, grenadiers, turbot, Norway haddock, bank-clams, and anything else that is eatable and can be found in the same waters.' Frequently halibut may be seen chasing flatfish over the bottom of the water. About Cape Sable their favorite food seems to be haddock and cusk. A very singular mode of attacking a cod has been recorded by Captain Collins, an experienced fisherman and good observer. They often kill their prey by blows of the tail, a fact which is quite novel and interesting. He has described an instance which occurred on a voyage home from Sable Island in 1877: 'The man at the wheel sang out that he saw a halibut flapping its tail about a quarter of a mile off our starboard quarter. I looked through the spy-glass and his statement was soon verified by the second appearance of the tail. We hove out a dory, and two men went with her, taking with them a pair of gaff-hooks. They soon returned, bringing not only the halibut, which was a fine one of about seventy pounds weight, but a small codfish which it had been trying to kill by striking it with its tail. The codfish was quite exhausted by the repeated blows and did not attempt to escape after its enemy had been captured. The halibut was so completely engaged in the pursuit of the codfish that it paid no attention to the dory and was easily captured.'

"The females become heavy with roe near the middle of the year, and about July and August are ready to spawn, although 'some fishermen say that they spawn at Christmas' or 'in the month of January, when they are on the shoals.' The roe of a large halibut which weighed 356 pounds weighed 44 pounds, and indeed the 'ovaries of a large fish are too heavy to be lifted by a man without considerable exertion, being often 2 feet or more in length.' A portion of the roe 'representing a fair average of the eggs, was weighed and found to contain 2185 eggs,' and the entire number would be 2,182,773."

Closely allied to the halibut are numerous smaller forms with more elongate body. The Greenland halibut, Reinhardtius hippoglossoides, and the closely related species in Japan, Reinhardtius matsuuræ, differ from the halibut most obviously in the straight lateral line. The arrow-toothed halibut, Atheresthes stomias, lives in deeper waters in the North Pacific. Its flesh is soft, the mouth very large, armed with arrow-shaped teeth. The head in this species is less distorted than in any of the others, the upper eye being on the edge of the disk in front of the dorsal fin. For this reason it has been supposed to be the most primitive of the living species, but these traits are doubtless elusive and a result of degeneration.

Eopsetta jordani is a smaller halibut-like fish, common on the coast of California, an excellent food-fish, with firm white flesh, sold in San Francisco restaurants under the very erroneous name of "English sole." Large numbers are dried by the Chinese for export to China. A similar species, Hippoglossoides platessoides, known as the "sand-dab," is common on both shores of the North Atlantic, and several related species are found in the North Pacific. Verasper variegatus of Japan is notable for its bright coloration, the lower side being largely orange-red.

In the bastard halibuts, Paralichthys, the eyes and color are on the left side. These much resemble the true halibut, but are smaller and inferior as food, besides differing in details of structure. The Monterey halibut (Paralichthys californicus) is the largest of these, reaching a weight of sixty pounds. This species and one other from California (Xystreurys liolepis), normally left-sided, differ from all the other flounders in having the eyes almost as often on the right side as on the left side, as usual or normal in their type. The summer flounder (Paralichthys dentatus) replaces the Monterey halibut on the Atlantic Coast, where it is a common food-fish. Farther south it gives way to the Southern flounder (Paralichthys lethostigma) and the Gulf flounder, Paralichthys albigutta. In Japan Paralichthys olivaceus is equally common, and in western Mexico Paralichthys sinaloæ. The four-spotted flounder of New England, Paralichthys oblongus, belongs to this group. Similar species constituting the genus Pseudorhombus abound in India and Japan.

=The Plaice Tribe: Pleuronectinæ.=—The plaice tribe pass gradually into the halibut tribe, from which they differ in the small mouth, in which the blunt teeth are mostly on the blind side. The eyes are on the right side, the vertebræ are numerous, and the species live only in the cold seas, none being found in the tropics. In most of the Pacific species the lateral line has an accessory branch along the dorsal fin. The genus Pleuronichthys, or frog-flounders, has the teeth in bands. Pleuronichthys cornutus is common in Japan and three species, Pleuronichthys cœnosus being the most abundant, are found on the coast of California. Closely related to these is the diamond-flounder, Hypsopsetta guttulata of California. Parophrys vetulus is a small flounder of California, so abundant as to have considerable economic value. Lepidopsetta bilineata, larger and rougher, is almost equally common. It is similar to the mud-dab (Limanda limanda) of northern Europe and the rusty-dab (Limanda ferruginea) of New England.

The plaice, Pleuronectes platessa, is the best known of the European species of this type, being common in most parts of Europe and valued as food. Closely related to the plaice is a second species of southern Europe also of small size, Flesus flesus, to which the name flounder is in England especially applied. The common winter flounder of New England, Pseudopleuronectes americanus, is also very much like the plaice, but with more uniform scales. It is an important food-fish, the most abundant of the family about Cape Cod. The eel-back flounder, Liopsetta putnami, also of New England, is frequently seen in the markets. The males of this species have scattered rough scales, while the females are smooth. The great starry flounder of Alaska, Platichthys stellatus, is the largest of the small-mouthed flounders and in its region the most abundant. On the Pacific coast from Monterey to Alaska and across to northern Japan it constitutes half the catch of flounders. The body is covered with rough scattered scales, the fins are barred with black. It reaches a weight of twenty pounds. Living in shallow waters, it ascends all the larger rivers.

An allied species in Japan is Kareius bicoloratus, with scattered scales. Clidoderma asperrimum, also of northern Japan, has the body covered with series of warts.

In deeper water are found the elongate forms known as smear-dab and flukes. The smear-dab of Europe (Microstomus kitt) is rather common in deep water. Its skin is very slimy, but the flesh is excellent. The same is true of the slippery sole, Microstomus pacificus, of California and Alaska, and of other species found in Japan. Glyptocephalus cynoglossus, the craig-fluke, or pole-flounder, of the North Atlantic, is taken in great numbers in rather deep water on both coasts. Its flesh is much like that of the sole. A similar species (Glyptocephalus zachirus) with a very long pectoral on the right scale is found in California, and Microstomus kitaharæ in Japan.

=The Soles: Soleidæ.=—The soles (Soleidæ) are degraded flounders, the typical forms bearing a close relation to the plaice tribe, from which they may be derived. There are three very different groups or tribes of soles, and some writers have thought that these are independently derived from different groups of flounders. This fact has been urged as an argument against the recognition of the Soleidæ as a family separate from the flounders. If clearly proved, the soles should either be joined with the flounders in one family or else they should be divided into two or three, according to their supposed origin.

The soles as a whole differ from the flounders in having the bones of the head obscurely outlined, their edges covered by scales. The gill-openings are much reduced, the eyes small and close together, the ventral fins often much reduced, and sometimes the pectoral or caudal also. The mouth is very small, much twisted, and with few teeth.

The species of sole, about 150 in number, abound on sandy bottoms in the warm seas along the continents, very few being found about the Oceanic Islands. The three subfamilies, or tribes, may be designated as broad soles, true soles, and tongue-fishes.

=The Broad Soles: Achirinæ.=—The American soles (Achirinæ), or broad soles, resemble the smaller members of the turbot tribe of flounders, having the ventral fin of the eyed side extended along the ridge of the abdomen. The eyes and color are, however, on the right side. The eyes are separated by a narrow interorbital ridge. In most of these forms the body is broad and covered with rough scales. The species are mostly less than six inches long, and nearly all are confined to the warmer parts of America, many of them ascending the rivers. A very few (Aseraggodes, Pardachirus) are found in Japan and China. Some are scaleless and some have but a single small gill-opening on the blind side. The principal genus is Achirus. Achirus fasciatus, the common American sole, or hog-choker, is abundant from Boston to Galveston. Achirus lineatus and other species are found in the West Indies and on the west coast of Mexico. Almost all the species of Achirus are banded with black and the pectorals are very small or wanting altogether. All these species are practically useless as food from their very small size.

=The European Soles (Soleinæ).=—The European soles are more elongate in form, with the ventral fins narrow and not extended along the ridge of the abdomen. The eyes are on the right side with no bony ridge between them. No species of this type is certainly known from American waters, although numerous in Europe and Asia. The species have much in common with the plaice tribe of flounders and may be derived from the same stock. One species, as above noted, is found in the Miocene.

The common sole of Europe, Solea solea, is one of the best of food-fishes, reaching a length, according to Dr. Gill, of twenty-six inches and a weight of nine pounds. As usually seen in the markets it rarely exceeds a pound. It is found from Norway to Italy, and when properly cooked is very tender and delicate, superior to any of the flounders. According to Dr. Francis Day, it appears to prefer sandy or gravelly shores, but is rather uncertain in its migrations, for, although mostly appearing at certain spots almost at a given time, and usually decreasing in numbers by degrees, in other seasons they disappear at once, as suddenly as they arrive. Along the British seacoast they retire to the deep as frosts set in, revisiting the shallows about May if the weather is warm, their migrations being influenced by temperature. The food of the sole is to a considerable extent molluscous, but it is also said to eat the eggs and fry of other fishes and sea-urchins.

The spawning season is late in the year and during the spring months. The ova are in moderate number; a sole of one pound weight has, according to Buckland, about 134,000 eggs. The newly hatched, according to Dr. Day, do not appear to be commonly found so far out at sea as some other species. They enter into shallow water at the edge of the tide and are very numerous in favorable localities.

As is well known, the sole is one of the most esteemed of European fishes. In the words of Dr. Day, "the flesh of this fish is white, firm, and of excellent flavor, those from the deepest waters being generally preferred. Those on the west coast and to the south are larger, as a rule, than those towards the north of the British islands. In addition to its use as food, it is available for another purpose. The skin is used for fining coffee, being a good substitute for isinglass, and also as a material for artificial baits.

"The markets are generally supplied by the trawl. The principal English trawling-ground lies from Dover to Devonshire. They may be taken by spillers, but are not commonly captured with hooks; it is suggested that one reason may be that spillers are mostly used by day, whereas the sole is a night feeder. They are sometimes angled for with the hook, baited with crabs, worms, or mollusks; the most favorable time for fishing is at night, after a blow, when the water is thick, while a land breeze answers better than a sea breeze."

Several smaller species of sole are found in Europe. In Japan Zebrias zebra, black-banded, and Usinosita japonica, known as Usinóshita, or cow's tongue, are common. Farther south are numerous species of Synaptura and other genera peculiar to the Indian and Australian regions.

=The Tongue-fishes: Cynoglossinæ.=—The tongue-fishes are soles having the eyes on the left side not separated by a bony ridge, the two being very small and apparently in the same socket. The body is lanceolate, covered usually with rough scales, and as often with two or three lateral lines as with one. The species are mostly Asiatic. Cynoglossus robustus and other species are found in Japan, and in India are many others belonging to Cynoglossus and related genera. The larger species are valued as food. The single European species Symphurus nigrescens, common in the Mediterranean, is too small to have any value. Symphurus plagiusa, the tongue-fish of our coast, is common on our sandy shores from Cape Hatteras southward. Symphurus plagusia, scarcely different, replaces it in the West Indies. Symphurus atricandus is found in San Diego Bay, and numerous other species of no economic importance find their place farther south.

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XXVIII. SUBORDER JUGULARES

=THE Jugular-fishes.=—In all the families of spiny-rayed fishes, as ranged in order in the present work, from the Berycidæ to the Soleidæ, the ventrals are thoracic in position, the pelvis, if present, being joined to the shoulder-girdle behind the symphysis of the clavicles so that the ventral fin falls below or behind the pectoral fin. To this arrangement the families of Bembradidæ and Pinguipedidæ offer perhaps the only exceptions.

In all the families which precede the Berycidæ in the linear series adopted in this work, the ventral fins when present are abdominal, the pelvis lying behind the clavicles and free from them as in the sharks, the reptiles, and all higher vertebrates.

In all the families remaining for discussion, the ventrals are brought still farther forward to a point distinctly before the pectorals. This position is called jugular (Lat. jugulum, throat).

The fishes with jugular ventrals we here divide into six groups, orders, and suborders: Jugulares, Haplodoci, Xenopterygii, Anacanthini, Opisthomi, and Pediculati. The last two groups, and perhaps the Anacanthini also, may well be considered as distinct orders, being more aberrant than the others.

For the most primitive and at the same time most obscurely defined of these groups we may retain the term applied by Linnæus to all of them, the name Jugulares. This group includes those jugular-fishes in which the position of the gills, the structure of the skull, and the form of the tail are essentially as in ordinary fishes. It is an extremely diversified and perhaps unnatural group, some of its members resembling Opisthognathidæ and Malacanthidæ, others suggesting the mailed-cheek fishes, and still others more degenerate. The fishes having the fins thus placed were long ago set apart by Linnæus, under the name of "Jugulares," Callionymus being the genus first placed by him in this group. Besides their anterior insertion, the ventrals in the Jugulares are more or less reduced in size, the rays being usually but not always less than I, 5 in number and more often reduced to one or two, or even wholly lost.

In general, the jugular fishes are degenerate as compared with the perch-like forms, but in certain regards they are often highly specialized. The groups showing this character are probably related one to another, but in some cases this fact is not clearly shown. In most of the jugular-fishes the shoulder-girdle shows some change or distortion. The usual foramen in the hypercoracoid is often wanting or relegated to the interspace between the coracoids, and the arrangement of the actinosts often deviates from that seen in the perciform fishes.

=The Weevers: Trachinidæ.=—Of the various families the group of weevers, Trachinidæ, most approaches the type of ordinary fishes. In the words of Dr. Gill, these fishes are known by "an elongated body attenuated backward from the head, compressed, oblong head, with the snout very short, a deeply cleft, oblique mouth, and a long spine projecting backward from each operculum and strengthened by extension on the surface of the operculum, as a keel. The dorsal fins are distinct, the first composed of strong, pungent spines radiating from a short base and about six or seven in number. The second dorsal and anal are very long. The pectorals have the lower rays unbranched, and the ventrals are in advance of the pectorals, and have each a spine and five rays. The species of this family are mostly found along the European and western African coast; but singularly enough a species closely related to the Old World form is found on the coast of Chile. None have been obtained from the intermediate regions or from the American coast. Two species are found in England, and are known under the name of the greater weever (Trachinus draco), about twelve inches long, and the lesser weever (Trachinus vipera), about six inches long. They are perhaps the most dreaded of the smaller English fishes. The formidable opercular spines are weapons of defense, and when seized by the fisherman the fish is apt to throw its head in the direction of the hand and lance a spine into it. The pungent dorsal spines are also defensive. Although without a poison gland, such as some fishes distantly related have at the base of the spines, they cause very severe wounds, and death may occur from tetanus. They are therefore divested of both opercular and dorsal spines before being exposed for sale. The various popular names which the weevers enjoy, in addition to their general designation, mostly refer to the armature of the spines, or are the result of the armature; such are adder-fish, stingfish, and sting-bull."

No species of Trachinidæ is known from North America or from Asia. In these fishes, as Dr. Boulenger has lately shown, the hypercoracoid is without foramen, the usual perforation lying between this bone and the hypercoracoid. A similar condition exists in the Anacanthini, or codfishes, but it seems to have been developed independently in the two groups. In the relatives of the Trachinidæ the position of this foramen changes gradually, moving by degrees from its usual place to the lower margin of the hypercoracoid. Species referred to Trachinus are recorded from the Miocene as well as Trachinus.

The extinct group of Callipterygidæ found in the Eocene of Monte Bolca seems allied to the Trachinidæ. It has the dorsal fin continuous, the spines small, the soft rays high; the scales are very small or wanting. Callipteryx speciosus and C. recticandus are the known species.

=The Nototheniidæ.=—In the family of Nototheniidæ the foramen is also wanting or confluent with the suture between the coracoids. To this family belong many species of the Antarctic region. These are elongate fishes with ctenoid scales and a general resemblance to small Hexagrammidæ. In most of the genera there is more than one lateral line. These species are the antipodes of the Cottidæ and Hexagrammidæ; although lacking the bony stay of the latter, they show several analogical resemblances and have very similar habits.

The Harpagiferidæ, naked, with the opercle armed with spines, and resemble sculpins even more closely than do the Nototheniidæ. Harpagifer is found in Antarctic seas, and the three species of Draconetta in the deeper waters of the North Atlantic and Pacific. These little fishes resemble Callionymus, but the opercle, instead of the preopercle, bears spines. The Bovichthyidæ of New Zealand are also sculpin-like and perhaps belong to the same family. Dr. Boulenger places all these Antarctic forms with the foramen outside the hypercoracoid in one family, Nototheniidæ. Several deep-sea fishes of this type have been lately described by Dr. Louis Dollo and others from the Patagonian region. One of these forms, Macrias amissus, lately named by Gill and Townsend, is five feet long, perhaps the largest deep-sea fish known. The family of Percophidæ, from Chile, is also closely allied to these forms, the single species differing in slight respects of osteology.

Closely related to the family of Nototheniidæ and perhaps scarcely distinct from it is the small family of Pteropsaridæ, which differs in having but one lateral line and the foramen just above the lower edge of the hypercoracoid. The numerous species inhabit the middle Pacific, and are prettily colored fishes, looking like gobies. Pteropsaron is a Japanese genus, with high dorsal and anal fins; Parapercis is more widely diffused. Osurus schauinslandi is one of the neatest of the small fishes of Hawaii. Several species of Parapercis and Neopercis occur in Japan and numerous others in the waters of Polynesia. Pseudeleginus majori of the Italian Miocene must belong near Parapercis.

The Bathymasteridæ, or ronquils, are perhaps allied to the Nototheniidæ; they resemble the Opisthognathidæ, but the jaws are shorter and they have a large number of vertebræ as befits their northern distribution. Ronquilus jordani is found in Puget Sound and Bathymaster signatus in Alaska. The ventral rays are I, 5, and the many-rayed dorsal has a few slender spines in front.

=The Leptoscopidæ.=—The Leptoscopidæ of New Zealand resemble the weevers and star-gazers, but the head is unarmed, covered by thin skin.

=The Star-gazers: Uranoscopidæ.=—The Uranoscopidæ, or star-gazers, have the head cuboid, mostly bony above, the mouth almost vertical, the lips usually fringed, and the eyes on the flat upper surface of the head. The spinous dorsal is short and may be wanting. The hypercoracoid has a foramen, and the body is naked or covered with small scales. The appearance is eccentric, like that of some of the Scorpænidæ, but the anatomy differs in several ways from that of the mailed-cheek fishes.

The species inhabit warm seas, and the larger ones are food-fishes of some importance. One species, Uranoscopus scaber, abounds in the Mediterranean. Uranoscopus japonicus and other species are found in Japan. Astroscopus y-græcum is the commonest species on our Atlantic coast. The bare spaces on the top of the head in this species yield vigorous electric shocks. Another American species is Astroscopus guttatus. In Japan and the East Indies the forms are more numerous and varied. Ichthyscopus lebeck, with a single dorsal, is a fantastic inhabitant of the seas of Japan, and Anema monopterygium in New Zealand.

Uranoscopus peruzzii, an extinct star-gazer, has been described from the Pliocene of Tuscany.

=The Dragonets: Callionymidæ.=—Remotely allied to the Uranoscopidæ is the interesting family of dragonets, or Callionymidæ. These are small scaleless fishes with flat heads, the preopercle armed with a strong spine, the body bearing a general resemblance to the smaller and smoother Cottidæ. The gill-openings are very small, the ventral fins wide apart. The colors are highly variegated, the fins are high, often filamentous, and the sexes differ much in coloration and in the development of the fins. The species are especially numerous on the shores of Japan, where Callionymus valenciennesi, Callionymus beniteguri, and Calliurichthys japonicus are food-fishes of some slight importance. Others are found in the East Indies, and several large and handsome forms are taken in the Mediterranean. Callionymus draco, the dragonet, or "sculpin," reaches the coast of England. In America but three species have been taken. These are dredged in deep water in the East Indies. In other parts of the world these fantastic little creatures are shore-fishes, creeping about in the shallow bays. Species of Synchiropus, colored like the coral sands, abound in the Polynesian coral reefs.

A fossil species of Callionymus (C. macrocephalus) are found in the Miocene of Croatia.

The family of Rhyacichthyidæ is a small group of Asiatic fishes allied to the Callionymidæ, but less elongate and differing in minor details. They are found not in the sea, but in mountain streams. Rhyacichthys (formerly called by the preoccupied name Platyptera) is the principal genus.

The Trichonontidæ, with wide gill-openings and cycloid scales, are also related to the Callionymidæ. The species are few, small, and confined to the Indian and Australian seas. Another small family closely related to this is the group of Hemerocœtidæ of the same region.

=The Dactyloscopidæ.=—In this and the preceding families of jugular fishes the ventral rays remain I, 5, as in the typical thoracic forms. In most of the families yet to be described the number is I, 3, a character which separates the little fishes of the family of Dactyloscopidæ from the Uranoscopidæ and Leptoscopidæ. Dactyloscopus tridigitatus is a small fish of the coral sands of Cuba. The other species of this family are found mostly in the West Indies and on the west coast of Mexico. Several genera, Myxodagnus, Gillellus, Dactylagnus, etc., are recognized. In the structure of the shoulder-girdle these species diverge from the star-gazers, approaching the blennies, and their position is intermediate between Trachinidæ and Blenniidæ.

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XXIX. THE BLENNIES: BLENNIIDÆ

THE great family of blennies, Blenniidæ, contains a vast number of species with elongate body, numerous dorsal spines, without suborbital stay or sucking-disk, and the ventrals jugular, where present, and of one spine and less than five soft rays. Most of them are of small size, living about rocks on the sea-shores of all regions. In general they are active fishes, of handsome but dark coloration, and in the different parts of the group is found great variety of structure. The tropical forms differ from those of arctic regions in the much shorter bodies and fewer vertebræ. These forms are most like ordinary fishes in appearance and structure and are doubtless the most primitive. Of the five hundred known species of blennies, we can note only a few of the most prominent. To Clinus and related genera belong many species of the warm seas, scaly and ovoviviparous, at least for the most part. The largest of these is the great kelpfish of the coast of California, Heterostichus rostratus, a food-fish of importance, reaching the length of two feet. Others of this type scarcely exceed two inches. Neoclinus satiricus, also of California, is remarkable for the great length of the upper jaw, which is formed as in Opisthognathus. Its membranes are brightly colored, being edged with bright yellow. Gibbonsia elegans is the pretty "señorita" of the coralline-lined rock-pools of California. Lepisoma nuchipinne, with a fringe of filaments at the nape, is very abundant in rock-pools of the West Indies. The species of Auchenopterus abound in the rock-pools of tropical America. These are very small neatly colored fishes with but one soft ray in the long dorsal fin. Species of Tripterygion, Myxodes, Cristiceps, and other genera abound in the South Pacific.

In Blennius and its relatives the body is scaleless and the slender teeth are arranged like the teeth of a comb. In most species long, fang-like posterior canines are developed in the jaws. Blennius is represented in Europe by many species, Blennius galerita, ocellaris, and basiliscus being among the most common. Certain species inhabit Italian lakes, having assumed a fresh-water habit. The numerous American species mostly belong to other related genera, Chasmodes bosquianus being most common. Blennius yatabei abounds in Japan. In Petroscirtes and its allies the gill-openings are much restricted. The species are mainly Asiatic and Polynesian and are very prettily colored. Petroscirtes elegans and P. trossulus adorn the Japanese rock-pools and others, often deep blue in color, abound in the coral reefs of Polynesia.

The rock-skippers (Salarias, Alticus, etc.) are herbivorous, with serrated teeth set loosely in the jaws. These live in the rock-pools of the tropics and leap from rock to rock when disturbed with the agility of lizards. They are dusky or gray in color with handsome markings. One of them, Erpichthys or Alticus saliens in Samoa, lives about lava rocks between tide-marks, and at low tide remains on the rocks, over which it runs with the greatest ease and with much speed, its movements being precisely like those of Periophthalmus. As in the species of the latter genus, otherwise wholly different, this Alticus has short ventral fins padded with muscle.

Erpichthys atlanticus is found in abundance on both coasts of tropical America. Many species abound in Polynesia and in both Indies. Salarias enosimæ lives in the clefts of lava rocks on the shores of Japan. Ophioblennius (webbi) is remarkable for its strong teeth, Emblemaria (nivipes, Atlantica) for its very high dorsal. Many other genera allied to Blennius, Clinus, and Salarias abound in the warm seas.

=The Northern Blennies: Xiphidiinæ, Stichæiniæ, etc.=—The blennies of the north temperate and arctic zones have the dorsal fin more elongate, the dorsal fin usually but not always composed entirely of spines. The scales are small and the ventral fins generally reduced in size. These are divided by Dr. Gill into several distinct families, but the groups recognized by him are subject to intergradations.

Chirolophis (ascanii) of north Europe is remarkable for the tufted filaments on the head. These are still more developed in Bryostemma of the North Pacific, Bryostemma polyactocephalum and several other species being common from Puget Sound to Japan. Apodichthys (flavidus) of California is remarkable for a large quill-shaped anal spine and for the great variation in color, the hue being yellow, grass-green, or crimson, according to the color of the algæ about it. There is no evidence, however, that the individual fish can change its color, and these color forms seem to be distinct races within the species. Xererpes fucorum of California lies quiescent in the seaweed (Fucus) after the tide recedes, its form, color, and substance seeming to correspond exactly with those of the stems of algæ. Pholis gunnellus is the common gunnel (gunwale), or butter-fish, of both shores of the North Atlantic, with numerous allies in the North Pacific. Of these, Enedrias nebulosus, the ginpo, or silver-tail, is especially common in Japan. Xiphidion and Xiphistes of the California coast, and Dictyosoma of Japan, among others, are remarkable for the great number of lateral lines, these extending crosswise as well as lengthwise. Cebedichthys violaceus, a large blenny of California, has the posterior half of the dorsal made of soft rays. Opisthocentrus of Siberia and north Japan has the dorsal spines flexible, only the posterior ones being short and stiff. The snake-blennies (Lumpenus), numerous in the far North, are extremely slender, with well-developed pectorals and ventrals. Lumpenus lampetræformis is found on both shores of the Atlantic. In Stichæus a lateral line is present. There is none in Lumpenus, and in Ernogrammus and Ozorthe there are three. All these are elongate fishes, of some value as food and especially characteristic of the Northern seas. Fossil blennies are almost unknown. Pterygocephalus paradoxus of the Eocene resembles the living Cristiceps, a genus which differs from Clinus in having the first few dorsal spines detached, inserted on the head. The first spine alone in Pterygocephalus is detached and is very strong. A species called Clinus gracilis is described from the Miocene near Vienna, Blennius fossilis from the Miocene of Croatia, and an uncertain Oncolepis isseli from Monte Bolca. The family is certainly one of the most recent in geologic times. The family of Blenniidæ, as here recognized, includes a very great variety of forms and should perhaps be subdivided into several families, as Dr. Gill has suggested. At present there is, however, no satisfactory basis of division known.

=The Quillfishes: Ptilichthyidæ.=—The Ptilichthyidæ, or quillfishes, are small and slender blennies of the North Pacific, with very numerous fin-rays. Ptilichthys goodei has 90 dorsal spines and 145 soft rays. Another group of very slender naked blennies is the small family of Xiphasiidæ from the South Pacific. The jaws have excessively long canines; there are no ventral fins. The dorsal fin is very high and the caudal ends in a long thread.

=The Blochiidæ.=—Of doubtful relationship is the extinct family of Blochiidæ. In this group the body is elongate, covered with keeled plates imbricated like shingles. The dorsal is composed of many slender spines, and the vertebræ much elongate. In Blochius longirostris (Monte Bolca Eocene) has very long jaws, lined with small teeth. Zittel regards the family as allied to the Belonorhynchidæ, but the prolongation of the jaws may be a character of analogy merely. Woodward places it next to the Blenniidæ, supposing it to have small and jugular ventral fins. But as the presence of ventral fins is uncertain, the position of the family cannot be ascertained and it may really belong in the neighborhood of Ammodytes. The dorsal rays are figured by Woodward as simple.

=The Patæcidæ etc.=—The Patæcidæ are blenny-like fishes of Australia, having the form of Congriopus, the spinous dorsal being very high and inserted before the eyes, forming a crest. Patæcus fronto is not rare in South Australia. The Gnathanacanthidæ is another small group of peculiar blennies from the Pacific. The Acanthoclinidæ are small blennies of New Zealand with numerous spines in the anal fin. Acanthoclinus littoreus is the only known species.

=The Gadopsidæ, etc.=—The family of Gadopsidæ of the rivers of New Zealand and southern Australia consists of a single species, Gadopsis marmoratus, resembling the scaly blennies called Clinus, but with long ventrals of a single ray, and three spines in the anal fin besides other peculiarities. The species is locally very common and with various other fishes in regions where true trout are unknown, it is called "trout."

The Cerdalidæ are small band-shaped blennies of the Pacific coast of Panama. The slender dorsal spines pass gradually into soft rays. Three species are known.

The wrymouths, or Cryptacanthodidæ, are large blennies of the northern seas, with the mouth almost vertical and the head cuboid. The wrymouth or ghostfish, Cryptacanthodes maculatus, is frequently taken from Long Island northward. It is usually dusky in color, but sometimes pure white. Other genera are found in the north Pacific.

=The Wolf-fishes: Anarhichadidæ.=—The wolf-fishes (Anarhichadidæ) are large blennies of the northern seas, remarkable for their strong teeth. Those in front are conical canines. Those behind are coarse molars. The dorsal is high, of flexible spines. The species are large, powerful, voracious fishes, known as wolf-fishes. Anarhichas lupus is the common wolf-fish of the north Atlantic, reaching a length of four to six feet, the body marked by dark cross-bands. Other similar species are found both in the north Pacific and north Atlantic. Anarhichas lepturus, plain brown in color, is common about the Aleutian Islands.

In the wolf-eel (Anarrhichthys ocellatus) of the coast of California, the head is formed as in Anarhichas but the body is band-shaped, being drawn out into a very long and tapering tail. This species, which is often supposed to be a "sea-serpent," sometimes reaches a length of eight feet. It is used for food. It feeds on sea-urchins and sand-dollars (Echinarachinius) which it readily crushes with its tremendous teeth.

The skull of a fossil genus, Laparus (alticeps), with a resemblance to Anarhichas, is recorded from the Eocene of England.

=The Eel-pouts: Zoarcidæ.=—The remaining blenny-like forms lack fin spines, agreeing in this respect with the codfishes and their allies. In all of the latter, however, the hypercoracoid is imperforate, the pseudobranchiæ are obsolete, and the tail isocercal. The forms allied to Zoarces and Ophidion, and which we may regard as degraded blennies, have homocercal (rarely leptocercal) tails, generally but not always well-developed pseudobranchiæ and the usual foramen in the hypercoracoid.

The Zoarcidæ, or eel-pouts, have the body elongate, naked, or covered with small scales, the dorsal and anal of many soft rays and the gill-openings confined to the side. Most of the species live in rather deep water in the Arctic and Antarctic regions. Zoarces viviparus, the "mother of eels," is a common fish of the coasts of northern Europe. In the genus Zoarces, the last rays of the dorsal are short and stiff, like spines. The species are viviparous; the young being eel-like in form, the name "mother of eels" has naturally arisen in popular language. The American eel-pout, sometimes called mutton-fish, Zoarces anguillaris, is rather common north of Cape Cod, and a similar species, Zoarces elongatus, is found in northern Japan. Lycodopsis pacifica, without spines in the dorsal, replaces Zoarces in California. The species of Lycodes, without spines in the dorsal, and with teeth on the vomer and palatines, are very abundant in the northern seas, extending into deep waters farther south. Lycodes reticulatus is the most abundant of these fishes, which are valued chiefly by the Esquimaux and other Arctic races of people. Numerous related genera are recorded from deep-sea explorations, and several others occur about Tierra del Fuego. Gymnelis, small, naked species brightly colored, is represented by Gymnelis viridis in the Arctic and by Gymnelis pictus about Cape Horn.

The family of Scytalinidæ contains a single species, Scytalina cerdale, a small snake-shaped fish which lives in wet gravel between tide-marks, on Waada Island near Cape Flattery in Washington, not having yet been found elsewhere. It dives among the wet stones with great celerity, and can only be taken by active digging.

To the family of Congrogadidæ belong several species of eel-shaped blennies with soft rays only, found on the coasts of Asia. Another small family, Derepodichthyidæ, is represented by one species, a scaleless little fish from the shores of British Columbia.

The Xenocephalidæ consist of a single peculiar species, Xenocephalus armatus, from the island of New Ireland. The head is very large, helmeted with bony plates and armed with spines. The body is short and slender, the ventrals with five rays, the dorsal and anal short.

=The Cusk-eels: Ophidiidæ.=—The more important family of Ophidiidæ, or cusk-eels, is characterized by the extremely anterior position of the ventral fins, which are inserted at the throat, each one appearing as a long forked barbel. The tail is leptocercal, attenuate, the dorsal and anal confluent around it. Ophidion barbatum and Rissola rochei are common in southern Europe. Rissola marginata is the commonest species on our Atlantic coast, and Chilara taylori in California. Other species are found farther south, and still others in deep water. Genypterus contains numerous species of the south Pacific, some of which reach the length of five feet, forming a commercial substitute for cod. Genypterus capensis is the klipvisch of the Cape of Good Hope, and Genypterus australis the "Cloudy Bay cod" or "rock ling" of New England. Another large species, Genypterus maculatus, occurs in Chile. A few fragments doubtfully referred to Ophidion and Fierasfer occur in the Eocene and later rocks. The Lycodapodidæ contain a few small, scaleless fishes (Lycodapus) dredged in the north Pacific.

=Sand-lances: Ammodytidæ.=—Near the Ophidiidæ are placed the small family of sand-lances (Ammodytidæ). This family comprises small, slender, silvery fishes, of both Arctic and tropical seas, living along shore and having the habit of burying themselves in the sand under the surf in shallow water. The jaws are toothless, the body scarcely scaly and crossed by many cross-folds of skin, the many-rayed dorsal fin is without spines, and the ventral fins when present are jugular. The species of the family are very much alike. From their great abundance they have sometimes much value as food, more perhaps as bait, still more as food for salmon and other fishes, from which they escape by plunging into the sand. Sometimes a falling tide leaves a sandy beach fairly covered with living "lants" looking like a moving foam of silver. Ammodytes tobianus is the sand-lance or lant of northern Europe. Ammodytes americanus, scarcely distinguishable, replaces it in America; and Ammodytes personatus in California, Alaska, and Japan. This is a most excellent pan fish, and the Japanese, who regard little things, value it highly.

In the genus Hyperoplus there is a large tooth on the vomer. In the tropical genera there is a much smaller number of vertebræ and the body is covered with ordinary scales instead of delicate, oblique cross-folds of skin. These tropical species must probably be detached from the Ammodytidæ to form a distinct family, Bleekeriidæ. Bleekeria kallolepis is found in India, Bleekeria gilli is from an unknown locality, and the most primitive species of sand-lance, Embolichthys mitsukurii, occurs in Formosa. In this species, alone of the sand-lances, the ventral fins are retained. These are jugular in position, as in the Zoarcidæ, and the rays are I, 3. The discovery of this species makes it necessary to separate the Ammodytidæ and Bleekeriidæ widely from the Percesoces, and especially from the extinct families of Crossognathidæ and Cobitopsidæ with which its structure in other regards has led Woodward, Boulenger, and the present writer to associate it.

Although an alleged sand-lance, Rhynchias septipinnis, with ventral fins abdominal, was described a century ago by Pallas, no one has since seen it, and it may not exist, or, if it exists, it may belong among the Percesoces. The relation of Ammodytes to Embolichthys is too close to doubt their close relationship. According to Dr. Gill the Ammodytidæ belong near the Hemerocœtidæ.

=The Pearlfishes: Fierasferidæ.=—In the little group of pearlfishes, called Fierasferidæ or Carapidæ, the body is eel-shaped with a rather large head, and the vent is at the throat. Numerous species of Fierasfer (Carapus) are found in the warm seas. These little fishes enter the cavities of sea-cucumbers (Holothurians) and other animals which offer shelter, being frequently taken from the pearl-oyster. In the Museum of Comparative Zoology, according to Professor Putnam, is "one valve of a pearl-oyster in which a specimen of Fierasfer dubius is beautifully inclosed in a pearly covering deposited on it by the oyster." A photograph of a similar specimen is given above. The species found in Holothurians are transparent in texture, with a bright pearly luster. Species living among lava rocks, as Jordanicus umbratilis of the south seas, are mottled black. Since this was written a specimen of this black species has been obtained from a Holothurian in Hilo, Hawaii, by Mr. H. W. Henshaw.

=The Brotulidæ.=—The Brotulidæ constitute a large family of fishes, resembling codfishes, but differing in the character of the hypercoracoid, as well as in the form of the tail. The resemblance between the two groups is largely superficial. We may look upon the Brotulidæ as degraded blennies, but the Gadidæ have an earlier and different origin which has not yet been clearly made out. Most of the Brotulidæ live in deep water and are without common name or economic relations. Two species have been landlocked in cave streams in Cuba, where they have, like other cavefishes, lost their sight, a phenomenon which richly deserves careful study, and which has been recently investigated by Dr. C. H. Eigenmann. These blind Brotulids, called Pez Ciego in Cuba, are found in different caves in the county of San Antonio, where they reach a length of about five inches. As in other blindfishes, the body is translucent and colorless. These species are known as Lucifuga subterranea and Stygicola dentata. They are descended from allies of the genera called Brotula and Dinematichthys. Brotula barbata is a cusk-like fish, occasionally found in the markets of Havana. Similar species, Brotula multibarbata and Sirembo inermis, are common in Japan, and Brosmophycis marginatus, beautifully red in color, is occasionally seen on the coast of California. Many other genera and species abound in the depths of the sea and in crevices of coral reefs, showing much variety in form and structure.

The Bregmacerotidæ are small fishes, closely related to the Brotulids, having the hypercoracoid perforate, but with several minor peculiarities, the first ray of the dorsal being free and much elongate. They live near the surface in the open sea. Bregmaceros macclellandi is widely diffused in the Pacific.

=Ateleopodidæ.=—The small family of Ateleopodidæ includes long-bodied, deep-water fishes of the Pacific, resembling Macrourus, but with smooth scales. The group has the coracoids as in Brotulidæ, and the actinosts are united in an undivided plate. Ateleopus japonicus is the species taken in Japan.

=Suborder Haplodoci.=—We may here place the peculiar family of Batrachoididæ, or toadfishes. It constitutes the suborder of Haplodoci (ἁπλόος, simple; δόκος, shaft) from the simple form of the post-temporal. This order is characterized by the undivided post-temporal bone and by the reduction of the gill-arches to three. A second bone behind the post-temporal connects the shoulder-girdle above to the vertebral column. The coracoid bones are more or less elongate, suggesting the arm seen in pediculate fishes.

The single family has the general form of the Cottidæ, the body robust, with large head, large mouth, strong teeth, and short spinous dorsal fin. The shoulder-girdle and its structures differ little from the blennioid type. There are no pseudobranchiæ and the tail is homocercal. The species are relatively few, chiefly confined to the warm seas and mostly American, none being found in Europe or Asia. Some of them ascend rivers, and all are carnivorous and voracious. None are valued as food, being coarse-grained in flesh. The group is probably nearest allied to the Trachinidæ or Uranoscopidæ.

Opsanus tau, the common toadfish, or oyster-fish, of our Atlantic coast, is very common in rocky places, the young clinging to stones by a sucking-disk on the belly, a structure which is early lost. It reaches a length of about fifteen inches. Opsanus pardus, the leopard toadfish, or sapo, of the Gulf coast, lives in deeper water and is prettily marked with dark-brown spots on a light yellowish ground.

In Opsanus the body is naked and there is a large foramen, or mucous pore, in the axil of the pectoral. In the Marcgravia cryptocentra, a large Brazilian toadfish, this foramen is absent. In Batrachoides, a South American genus, the body is covered with cycloid scales. Batrachoides surinamensis is a common species of the West Indies. Batrachoides pacifici occurs at Panama. The genus Porichthys is remarkable for the development of series of mucous pores and luminous spots in several different lateral lines which cover the body. These luminous spots are quite unlike those found in the lantern-fishes (Myctophidæ) and other Iniomi. Their structure has been worked out in detail by Dr. Charles Wilson Greene, a summary of whose conclusions are given on page 191, Vol. I.

The common midshipman, or singing fish, of the coast of California is Porichthys notatus. This species, named midshipman from its rows of shining spots like brass buttons, is found among rocks and kelp and makes a peculiar quivering or humming noise with its large air-bladder.

Porichthys porosissimus, the bagre sapo, is common on all coasts of the Gulf of Mexico and the Caribbean Sea. Porichthys margaritatus is found about Panama and Porichthys porosus in Chile.

The species of Thalassophryne and Thalassothia, the poison toadfishes, are found along the coasts of South America, where they sometimes ascend the rivers. In these species there is an elaborate series of venom glands connected with the hollow spines of the opercle and the dorsal spines. Dr. Günther gives the following account of this structure as shown in Thalassophryne reticulata, a species from Panama:

"In this species I first observed and closely examined the poison organ with which the fishes of this genus are provided. Its structure is as follows: (1) The opercular part: The operculum is very narrow, vertically styliform and very mobile; it is armed behind with a spine, eight lines long in a specimen of 10½ inches, and of the same form as the venom fang of a snake; it is, however, somewhat less curved, being only slightly bent upward. It has a longish slit at the outer side of its extremity which leads into a canal perfectly closed and running along the whole length of its interior; a bristle introduced into the canal reappears through another opening at the base of the spine, entering into a sac situated on the opercle and along the basal half of the spine; the sac is of an oblong-ovate shape and about double the size of an oat grain. Though the specimen had been preserved in spirits for about nine months it still contained a whitish substance of the consistency of thick cream, which on the slightest pressure freely flowed from the opening in the extremity of the spine. On the other hand, the sac could be easily filled with air or fluid from the foramen of the spine. No gland could be discovered in the immediate neighborhood of the sac; but on a more careful inspection I found a minute tube floating free in the sac, whilst on the left-hand side there is only a small opening instead of the tube. The attempts to introduce a bristle into this opening for any distance failed, as it appears to lead into the interior of the basal portion of the operculum, to which the sac firmly adheres at this spot. (2) The dorsal part is composed of the two dorsal spines, each of which is ten lines long. The whole arrangement is the same as in the opercular spines; their slit is at the front side of the point; each has a separate sac, which occupies the front of the basal portion; the contents were the same as in the opercular sacs, but in somewhat greater quantity. A strong branch of the lateral line ascends to the immediate neighborhood of their base. Thus we have four poison spines, each with a sac at its base; the walls of the sacs are thin, composed of a fibrous membrane, the interior of which is coated over with mucus. There are no secretory glands embedded between these membranes, and these sacs are probably merely the reservoirs in which the fluid secreted accumulates. The absence of a secretory organ in the immediate neighborhood of the reservoirs (an organ the size of which would be in accordance with the quantity of fluid secreted), the diversity of the osseous spines which have been modified into poison organs, and the actual communication indicated by the foramen in the sac lead me to the opinion that the organ of secretion is either that system of muciferous channels which is found in nearly the whole class of fishes, and the secretion of which has poisonous qualities in a few of them, or at least an independent portion of it. This description was made from the first example; through the kindness of Captain Dow I received two other specimens, and in the hope of proving the connection of the poison bags with the lateral-line system, I asked Dr. Pettigrew, of the Royal College of Surgeons, a gentleman whose great skill has enriched that collection with a series of the most admirable anatomical preparations, to lend me his assistance in injecting the canals. The injection of the bags through the opening of the spine was easily accomplished; but we failed to drive the fluid beyond the bag or to fill with it any other part of the system of muciferous channels. This, however, does not disprove the connection of the poison bags with that system, inasmuch as it became apparent that if there be minute openings they are so contracted by the action of the spirit in which the specimens were preserved as to be impassable to the fluid of injection. A great part of the lateral-line system consists of open canals; however, on some parts of the body, these canals are entirely covered by the skin; thus, for instance, the open lateral line ceases apparently in the suprascapular region, being continued in the parietal region. We could not discover any trace of an opening by which the open canal leads to below the skin; yet we could distinctly trace the existence of the continuation of the canal by a depressed line, so that it is quite evident that such openings do exist, although they may be passable only in fresh specimens. Thus likewise the existence of openings in the bags, as I believed to have found in the first specimen dissected, may be proved by examination of fresh examples. The sacs are without an external muscular layer and situated immediately below the loose thick skin which envelops their spines to their extremity. The injection of the poison into a living animal, therefore, can only be effected by the pressure to which the sac is subjected the moment the spine enters another body. Nobody will suppose that a complicated apparatus like the one described can be intended for conveying an innocuous substance, and therefore I have not hesitated to designate it as poisonous; and, Captain Dow informs me in a letter lately received, 'the natives of Panama seemed quite familiar with the existence of the spines and of the emission from them of a poison which, when introduced into a wound, caused fever, an effect somewhat similar to that produced by the sting of a scorpion; but in no case was a wound caused by one of them known to result seriously. The slightest pressure of the finger at the base of the spine caused the poison to jet a foot or more from the opening of the spine.' The greatest importance must be attached to this fact, inasmuch as it assists us in our inquiries into the nature of the functions of the muciferous system, the idea of its being a secretory organ having lately been superseded by the notion that it serves merely as a stratum for the distribution of peripheric nerves. Also the objection that the sting-rays and many Siluroid fishes are not poisonous because they have no poison organ cannot be maintained, although the organs conveying their poison are neither so well adapted for this purpose nor in such a perfect connection with the secretory mucous system as in Thalassophryne. The poison organ serves merely as a weapon of defense. All the Batrachoids with obtuse teeth on the palate and in the lower jaw feed on Mollusca and Crustaceans."

No fossil Batrachoididæ are known.

=Suborder Xenopterygii.=—The clingfishes, forming the suborder Xenopterygii (ξενός, strange; πτερύξ, fin), are, perhaps, allied to the toadfishes. The ventral fins are jugular, the rays I, 4 or I, 5, and between them is developed an elaborate sucking-disk, not derived from modified fins, but from folds of the skin and underlying muscles.

The structure of this disk in Gobiesox sanguineus is thus described by Dr. Günther:

"The whole disk is exceedingly large, subcircular, longer than broad, its length being (often) one-third of the whole length of the fish. The central portion is formed merely by skin, which is separated from the pelvic or pubic bones by several layers of muscles. The peripheric portion is divided into an anterior and posterior part by a deep notch behind the ventrals. The anterior peripheric portion is formed by the ventral rays, the membrane between them and a broad fringe which extends anteriorly from one ventral to the other. This fringe is a fold of the skin, containing on one side the rudimentary ventral spine, but no cartilage. The posterior peripheric portion is suspended on each side on the coracoid, the upper bone of which is exceedingly broad, becoming a free, movable plate behind the pectoral. The lower bone of the coracoid is of a triangular form, and supports a very broad fold of the skin, extending from one side to the other, and containing a cartilage which runs through the whole of that fold. Fine processes of the cartilage are continued into the soft striated margin, in which the disk terminates posteriorly. The face of the disk is coated with a thick epidermis, like the sole of the foot in higher animals. The epidermis is divided into many polygonal plates. There are no such plates between the roots of the ventral fins."

The body is formed much as in the toadfishes. The skin is naked and there is no spinous dorsal fin. The skeleton shows several peculiarities; there is no suborbital ring, the palatine arcade is reduced, as are the gill-arches, the opercle is reduced to a spine-like projection, and the vertebræ are numerous. The species are found in tide-pools in the warm seas, where they cling tightly to the rocks with their large ventral disks.

Several species of Lepadogaster and Mirbelia are found in the Mediterranean. Lepadogaster gouani is the best-known European species. Aspasma ciconiæ and minima occur about the rocks in the bays of Japan.

Most of the West Indian species belong to Gobiesox, with entire teeth, and to Arbaciosa, with serrated teeth. Some of these species are deep crimson in color, but most of them are dull olive. Gobiesox virgatulus is common on the Gulf Coast. Caularchus mæandricus, a very large species, reaching a length of six inches, abounds along the coast of California. Other genera are found at the Cape of Good Hope, especially about New Zealand. Chorisochismus dentex, from the Cape of Good Hope, reaches the length of a foot.

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XXX. OPISTHOMI AND ANACANTHINI

=ORDER Opisthomi.=—The order Opisthomi (ὄπισθη, behind; ὤμος, shoulder) is characterized by the general traits of the blennies and other elongate, spiny-rayed fishes, but the shoulder-girdle, as in the Apodes and the Heteromi, is inserted on the vertebral column well behind the skull.

The single family, Mastacembelidæ, is composed of eel-shaped fishes with a large mouth and projecting lower jaw, inhabiting the waters of India, Africa, and the East Indies. They are small in size and of no economic importance. The dorsal is long, with free spines in front and there are no ventral fins. Were these fins developed, they should in theory be jugular in position. There is no air-duct in Mastacembelus and it seems to be a true spiny-rayed fish, having no special relation to either Notacanthus or to the eels. Except for the separation of the shoulder-girdle from the skull, there seems to be no reason for separating them far from the Blennioid forms, and the resemblance to Notacanthus seems wholly fallacious.

Mastacembelus armatus is a common species of India and China. In Rhynchobdella the nasal appendage or proboscis, conspicuous in Mastacembelus, is still more developed. Rhynchobdella aculeata is common in India.

=Order Anacanthini.=—We may separate from the other jugular fishes the great group of codfishes and their allies, retaining the name Anacanthini (ἄνακανθος, without spine) suggested by Johannes Müller. In this group the hypercoracoid is without foramen, the fenestra lying between this bone and the hypocoracoid below it. The tail is isocercal, the vertebræ in a right line and progressively smaller backward, sometimes degenerate or whip-like (leptocercal) at tip. Other characters are shown in the structure of the skull. There are no spines in any of the fins; the ventrals are jugular, the scales generally small, and the coloration dull or brownish. The numerous species live chiefly in the northern seas, some of them descending to great depths. The resemblance of these fishes to some of the Blennioid group is very strongly marked, but these likenesses seem analogical only and not indicative of true affinity. The codfishes probably represent an early offshoot from the ancestors of the spiny-rayed fishes, and their line of evolution is unknown, possibly from Ganoid types. Among recent fishes there is nothing structurally nearer than the Nototheniidæ and Brotulidæ, but the line of descent must branch off much farther back than either of these. For the present, therefore, we may regard the codfishes and their allies (Anacanthini) as a distinct order.

=The Codfishes: Gadidæ.=—The chief family is that of the Gadidæ, or codfishes. These are characterized by a general resemblance to the common codfish, Gadus callarias. This is one of the best known of fishes, found everywhere on the shores of the North Atlantic, and the subject of economic fisheries of the greatest importance. Its flesh is white, flaky, rather tasteless, but takes salt readily, and is peculiarly well adapted for drying. The average size of the codfish is about ten pounds, but Captain Nathaniel Atwood of Provincetown records one with the weight of 160 pounds.

According to Dr. Goode:

"In the western Atlantic the species occurs in the winter in considerable abundance as far south as the mouth of the Chesapeake Bay, latitude 37°, and stragglers have been observed about Ocracoke Inlet. The southern limits of the species may be safely considered to be Cape Hatteras, in latitude 35° 10´. Along the coast of New England, the Middle States, and British North America, and upon all the off-shore banks of this region, cod are found usually in great abundance, during part of the year at least. They have been observed also in the Gulf of Bothnia, latitude 70° to 75°, and in the southeastern part of Baffin's Land to the northward of Cumberland Sound, and it is more than probable that they occur in the waters of the Arctic Sea to the north of the American continent, or away around to Bering Strait."

Dr. Gill says:

"The ocean banks of moderate depths are the favorite resorts of the cod, but it is by no means confined to those localities. The fish, indeed, occasionally enters into fresh, or at least brackish, water. According to Canadian authorities, it is found 'well up the estuary of the St. Lawrence, though how far up is not definitely stated, probably not beyond the limits of brackish water.' Even as far south as the Delaware River it has been known to enter the streams. Dr. C. C. Abbott records that in January, 1876, 'a healthy, strong, active codfish, weighing nearly four pounds, was taken in a draw-net in the Delaware River near Trenton, New Jersey; the stomach of the fish showed that it had been in river-water several days. Many of them had been taken about Philadelphia between 1856 and 1869.'

"The cod ranks among the most voracious of ordinary fishes, and almost everything that is eatable, and some that is not, may find its way into its capacious maw. Years ago, before naturalists had the facilities that the dredge now affords, cods' stomachs were the favorite resort for rare shells, and some species had never been obtained otherwise than through such a medium, while many filled the cabinet that would not otherwise have been represented. In the words of Mr. Goode, 'codfish swallow bivalve fish of the largest size, like the great sea-clams, which are a favorite article of food on certain portions of the coast'; further, 'these shells are nested, the smaller inside of the larger, sometimes six or seven in a set, having been packed together in this compact manner in the stomachs of the codfish after the soft parts have been digested out. Some of them had shreds of the muscles remaining in them and were quite fresh, having evidently been but recently ejected by the fish.' Even banks of dead shells have been found in various regions, which are supposed to be the remains of mollusks taken by the cod. Shell-fishes, however, form probably but the smaller portion of its diet, and fishes of its own class contribute materially to its food,— such as the herring family, the capelin, etc.

"The codfish in its mode of reproduction exhibits some interesting peculiarities. It does not come on the coast to spawn, as was once supposed, but its eggs are deposited in mid-sea and float to the surface, although it does really, in many cases, approach the land to do so. Prof. C. O. Sars, who has discovered its peculiarities, 'found cod at a distance of twenty to thirty Norwegian miles from the shore and at a depth of from one hundred to one hundred and fifty fathoms.' The eggs thus confided to the mercy of the waves are very numerous; as many as 9,100,000 have been calculated in a seventy-five-pound fish. 'When the eggs are first seen in the fish they are so small as to be hardly distinguishable; but they continue to increase in size until maturity, and after impregnation have a diameter depending upon the size of the parent, varying from one-nineteenth to one-seventeenth of an inch. A five- to eight-pound fish has eggs of the smaller size, while a twenty-five-pound one has them between an eighteenth and a seventeenth.' There are about 190,000 eggs of the smaller size to a pound avoirdupois. They are matured and ejected from September to November."

Unlike most fishes, the cod spawns in cooling water, a trait also found in the salmon family.

The liver of the cod yields an easily digested oil of great value in the medical treatment of diseases causing emaciation.

The Alaska cod, Gadus macrocephalus, is equally abundant with the Atlantic species, from which it differs very slightly, the air-bladder or sounds being smaller, according to the fishermen, and the head being somewhat larger. This species is found from Cape Flattery to Hakodate in Japan, and is very abundant about the Aleutian Islands and especially in the Okhotsk Sea. With equal markets it would be as important commercially as the Atlantic cod. In the codfish (Gadus) and related genera there are three dorsal and two anal fins. In the codfish the lateral line is pale and the lower jaw shorter than the upper.

The haddock (Melanogrammus æglifinus) closely resembles the cod and is of similar quality as food. It is known at sight by the black lateral line. It is found on both shores of the Atlantic and when smoked is the "finnan haddie" of commerce.

The pollack, coalfish, or green cod (Pollachius carbonarius) is also common on both shores of the north Atlantic. It is darker than the cod and more lustrous, and the lower jaw is longer, with a smaller barbel at tip. It is especially excellent when fresh.

The whiting (Merlangus merlangus) is a pollack-like fish common on the British coasts, but not reaching the American shores. It is found in large schools in sandy bays. The Alaska pollack (Theragra chalcogramma) is a large fish with projecting lower jaw, widely diffused in the north Pacific and useful as a food-fish to the Aleutian peoples. It furnishes a large part of the food of the fur-seal (Callorhinus alascanus and C. ursinus) during its migrations. The fur-seal rarely catches the true codfish, which swims near the bottom. The wall-eyed pollack (Theragra fucensis) is found about Puget Sound. Smaller codfishes of this type are the wachna cod (Eleginus navaga) of Siberia and the Arctic codling (Boreogadus saida), both common about Kamchatka, the latter crossing to Greenland.

Several dwarf codfishes having, like the true cod, three dorsal fins and a barbel at the chin are also recorded. Among these are the tomcod, or frostfish, of the Atlantic (Microgadus tomcod), the California tomcod (Microgadus proximus), and Micromesistius poutassou of the Mediterranean. These little cods are valued as pan fishes, but the flesh is soft and without much flavor.

Other cod-like fishes have but two dorsals and one anal fin. Many of these occur in deep water. Among those living near shore, and therefore having economic value, we may mention a few of the more prominent. The codlings (Urophycis) are represented by numerous species on both shores of the Atlantic. Urophycis blennoides is common in the Mediterranean. Urophycis regius, on our South Atlantic coast, is said to exhibit electric powers in life, a statement that needs verification. In the Gulf of Mexico Urophycis floridanus is common. Farther north are the more important species Urophycis tenuis, called the white hake, and Urophycis chuss, the squirrel-hake. The ling (Molva molva) is found in deep water about the North Sea.

A related genus, Lota, the burbot, called also ling and, in America, the lawyer, is found in fresh waters. This genus contains the only fresh-water members of the group of Anacanthini.

The European burbot, Lota lota, is common in the streams and lakes of northern Europe and Siberia. It is a bottom fish, coarse in flesh and rather tasteless, eaten sometimes when boiled and soaked in vinegar or made into salad. It is dark olive in color, thickly marbled with blackish.

The American burbot, or lawyer (Lota maculosa), is very much like the European species. It is found from New England throughout the Great Lakes to the Yukon. It reaches a length of usually two or three feet and is little valued as food in the United States, but rises much in esteem farther north. The liver and roe are said to be delicious. In Siberia its skin is used instead of glass for windows. In Alaska, according to Dr. Dall, it reaches a length of six feet and a weight of sixty pounds.

The rocklings (Gaidropsarus and Enchelyopus) have the first dorsal composed of a band of fringes preceded by a single ray. The species are small and slender, abounding chiefly in the Mediterranean and the North Atlantic. The young have been called "mackerel-midges." Our commonest species is Enchelyopus cimbrius, found also in Great Britain.

The cusk, or torsk, Brosme brosme, has a single dorsal fin only. It is a large fish found on both shores of the North Atlantic, but rather rare on our coasts.

Fossil codfishes are not numerous. Fragments thought to belong to this family are found in English Eocene rocks.

Nemopteryx troscheli, from the Oligocene of Glarus, has three dorsal fins and a lunate caudal fin. Other forms have been referred with more or less doubt to Gadus, Brosmius, Strinsia, and Melanogrammus.

Gill separates the "three-forked hake" (Raniceps trifurcus) of northern Europe as a distinct family, Ranicipitidæ. In this species the head is very large, broad and depressed, differing in this regard from the codlings and hakes, which have also two dorsal fins. The deep-water genus, Bathyonus, is also regarded as a distinct family, Bathyonidæ.

=The Hakes: Merluciidæ.=—Better defined than these families is the family of hakes, Merluciidæ. These pike-like codfishes have the skull peculiarly formed, the frontal bones being paired, excavated above, with diverging crests continuous forward from the forked occipital crest. The species are large fishes, very voracious, without barbels, with the skeleton papery and the flesh generally soft. The various species are all very much alike, large, ill-favored fishes with strong teeth and a ragged appearance, the flesh of fair quality. Merluccius merluccius, the hake or stock-fish, is common in Europe; Merluccius bilinearis, the silver hake, is common in New England, Merluccius productus in California, and Merluccius gayi in Chile.

=The Grenadiers: Macrouridæ.=—The large family of grenadiers, or rat-tails, Macrouridæ, is confined entirely to the oceanic depths, especially of the north Atlantic and Pacific. The head is formed much as in the codfishes, with usually a barbel at the chin. There are two dorsals, the second like the anal being low, but the leptocercal tail is very long and tapering, ending in a filament without caudal fin. The scales are usually rough and spinous. The species are usually large in size, and dull gray or black in color.

The best-known genus is Macrourus. Macrourus berglax is found on both shores of the north Atlantic. Macrourus bairdi is abundant in off-shore dredgings from Cape Cod to Cuba. Macrourus cinereus, the pop-eye grenadier, outnumbers all other fishes in the depths of Bering Sea. Cœlorhynchus japonicus is often taken by fishermen in Japan. Coryphænoides rupestris is common in the north Atlantic. Bogoslovius clarki and Albatrossia pectoralis were dredged by the Albatross about the volcanic island of Bogoslof. Trachyrhynchus trachyrhynchus is characteristic of the Mediterranean. Nematonurus goodei is common in the Gulf Stream, and Dolloa longifilis is found off Japan. Other prominent genera are Bathygadus, Gadomus, Regania, and Steindachnerella.

The Murænolepidæ are deep-sea fishes, with minute eel-like scales, and no caudal fin. The ventrals are five-rayed and there are 10 pterygials.

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XXII. CHROMIDES AND PHARYNGOGNATHI…

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