An outline of the natural history of our shores

Front matter

I I » II

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Med

Chapter II

Classification, Anatomy and Physiology, Reproduction, etc. — Chief British Forms — Their Habitats — Plan for Identification, etc.

CHAPTER ITI

The C(elenterata . . . . . .29

Section 1. — The Actinozoa, Simple and Compound — Anatomy — Reproduction — Relation to the Corals — Corals, how built up — Illustrations from British Types

Section 2. — The Hydroid Zoophytes — Structure — Alternate Generations — Modes of Reproduction — Nutrition, etc.

Section 3. — The larger Medusae or Jelly-fishes — Structure

Sense Organs, etc. — Reproduction — Vast Methods of this accounting for sudden Swarms of these

The Chief British Types of Ccelenterates, their Habitats, etc.

IX

X

CONTENTS

Chapter IV Page

The Echinodermata . . . . . .60

Anatomy and Classification — The whole Series of British Species, their Habitats, etc. — Reproduction — Facilities offered by the Echini for watching the Fertilisation and Consequent Changes in the Egg

Chapter IX

Anatomy of Types (Lamellibranch, etc.) — Nutrition and Reproduction — Artificial Culture of the Oyster — The Nudibranchi and Opisthobranchi — Their develop-

CONTENTS xi

PAGE

CHAPTER IX — continued

ment, pointing to a Shell-bearing Ancestry — The Cephalopoda — Habits — Observations on Captive Specimens — Intelligence, Memory, Mimicry — Chief British Types of Molluscs— Their Habitats, etc.

Chapter XI

Balanoglossus — Its Form and Habits and Habitats — Foreshadowing of the Vertebrate Type — Species, Geographical Range, etc.

The Tunicates, Simple and Compound — Anatomy — Development — Relation to Vertebrata — Methods of obtaining and observing the free Tadpole Larvae —

The Chief British Species and their Habitats, etc.

Amphioxus — Its Anatomy, Analogy to Tunicates and V ertebrates — Localities — Erratic Occurrence

Chapter XII

Breeding Places — Mode of obtaining and determining the Eggs — Observing Development — Habits, etc. — Nest Builders — Male Incubators, Mimicry, etc.

The Chief British Forms and their Habitats — Observations on Seasonal and Sexual Changes in Coloration, etc. — Existing Confusion in Labrid;e — Sexes classed as “ Species,” etc.

The Marine Aquarium . ... .

Facility of Maintenance — Causes of the frequent Failures — Rearing Larval Forms, etc.

List of a few Books useful to the Beginner .

PAGE

Index

. 347

LIST OF ILLUSTRATIONS

The Shore. A Typical Rock Pool on the Jersey Coast

Frontispiece

FIGURE PAGE

1. Types of British Foraminifera . . . .9

2. Photo-micrograph of Foraminifera . . .11

3. Foraminifera, with Pseuclopodia exserted . .15

4. Sponge ( Tethya ) budding . . . .17

5. Sycandra ciliata . . . . . .19

6. Grcmtia Compressa . . . . .19

7. Halichondria panicea . . . . .20

8. Isodictya palmata . . . . .21

9. Grotto, with growing Sponges . . . .23

10. Diagram of Simple Sponge . . . .25

11. Diagram of Complex Sponge . . . .25

12. Spicules of Sponges . . . . .27

1 3. Hvdroid Zoophytes and Medusids . . .33

14. Dahlia Anemone ( Tealia ) . . . .38

15. Gorgonia verrucosa . . . . .43

10. Gorgonia with Tentacles exserted . . .45

17. Alcyonium with Tentacles exserted . . .46

18. Photo-micrograph of Section of Alcyonium, . . 49

19. Aglaophenia pluma . . . . .51

20. Haliclystus octoradiatus . . . . .53

21. Rhizostoma and Chrysaora . . . .55

22. Hormophora pomiformis . . . . .58

23. Urcister glacialis . . . . .63

24. Asterina gibbosa . . . . . .64

25. Solaster papposa . . . . . .65

26. Ophiura albida . . . . . .67

27. Feather-Star and its Development . . .69

28. Test and Teeth of Sea-urchin . . . .71

29. Echinus miliaris, at home . . . .73

xiii

XIV

LIST OF ILLUSTRATIONS

FIGURE PAGE

30. Echinus lividus . . . . . .75

31. Spatcmgus purpureus . . . . .76

32. Test of Spatangus . . . . .77

33. Cucumciria and Synapta . . . . .79

34. Plates of Cucumciria and Synapta . . .80

35. Sabellct pavonina and S. arenilega and their Tubes . 85

36. Types of Polychsete Worms . . . .87

37. Aphrodita aculeatci . . . . .89

38. Terebella and its Tube . . . . .99

39. Amphitrite Edwardsii . . . . .101

40. Chcetovterus variopedatus . . . .103

41. Membraniporci membranacea .... 106

42. Portion of M embranipora, enlarged . . . 107

43. Lepralia foliaceci . . . . .108

44. Lepas anatifera . . . . . .111

45. Development of Lepas . . . . .114

46. Acorn Barnacles . . . . .116

47. Isopod Crustaceans attacking Pish . . . 122

48. Types of Isopoda and Amphipoda . . .124

49. Common Lobster . . . . .126

50. The “ Burrowing Prawns ” . . . .129

51. Alpheus ruber and Nika edulis . . . .131

53. Common Shrimp, and Variety mimicking Surroundings . 137

54. The Crawfish. Palinurus . . . .138

55. Larva of Crawfish . . . . .139

56. Scyllarus arctus . . . . . .141

57. The Mantis Shrimp ( Squilla ) .... 142

58. Common Hermit Crab . . . . .145

59. Galathea strigosa . . . . .148

60. Porcellana. platycheles . . . . .149

61. The Great Stone Crab . . . . .151

62. Dromia vulgaris . . . . . .152

63. Development of Crab . . . . .155

64. Common Shore Crab . . . . .156

65. The Edible Crab . . . . .158

66 Pilumnus hirtellus . . . . .159

67. Xantho florida, male . . . . .161

LIST OF ILLUSTRATIONS

XV

FIGURE PAGE

68. Xantho florida. Female, at home . . .101

69. The Velvet Fiddler Crab . . . . .162

70. Polybius Henslowii . . . . .164

7 1 . Corystes ccissivelaunus . . . . .165

73. Gonoplax angulata . . . . .167

74. Maia squinado. Male . . . . .170

75. Maia squinado. Female, masking . . .170

76. Pisa tetraodon. Male and Female . . .171

77. Pisa tetraodon, masking . . . .171

79. Stenorhynchus Egyptius . . . . .174

80. Stenorhynchus Egyptius, masking . . .175

81. Acheus cranchii, masking and denuded . . .175

82. Inachus dorsettensis . . . . .177

83. Nymphon gracile . . . . . .179

84. Types of Lamellibranchiata . . . .187

85. Artificial Oyster Rearing ..... 193

86. Types of Gastropoda . . . . .201

87. Chiton discrepans ..... 202

88. Purpura lapillus, and its Egg Cases . . .208

89. Nassa reticulata, and its Egg Cases . . . 209

90. Aplysia punctata . . . . .211

91. Doris tuber culata . . . . .213

92. Eggs and Larvae of Doris . . . .215

93. Octopus vulgaris . . . . . .217

94. Month Parts of Octopus . . . . .219

95. Octopus swimming ..... 223

96. Sepiola rondettii ...... 225

98. Sepia officinalis . . . . . .227

99. Tentacle and Suckers of Sepia .... 228

100. Botryllus morio . . . . < .236

101. Botryllus schlosseri .... 237

102. Anatomy of Ascidian, and its larva . . 239

103. Ciona intestinalis .... 245

104. Diagram of Amphioxus ..... 246

105. Group of Smooth Blennies, at home . . 249

XVI

LIST OF ILLUSTRATIONS

FIGURE

100. Gobies, Male and Female, at home

107. Coitus bubalis ....

108. Centronotus gunellus

109. Motellci tricerrata

110. Lepadogaster , under Side .

111. Great Spotted Wrasse

112. Gasterosteus spinachia

113. The British Pipe-fishes

114. Portion of Armour of Pipe-fish

115. The Sand-eels ....

116. Dragonet, swimming

117. Dragonet, mimicking Surroundings

118. Rhombus punctatus

119. Boar Fish ( Capros aper) .

120. The Lumpsucker

121. Plume-footed Mite ( Rhincolopus plumipes)

122. The Plaice ....

123. Plaice, masking its' Outline

PAGE

257 259 262

265 267

274 279

AN OUTLINE OF THE

NATURAL HISTORY OF OUR

SHORES

INTRODUCTORY

Henry Lord Brougham, in a discourse on the objects and pleasures of science, says :

“ In order to fully understand the advantages and pleasures which are derived from an acquaintance with any science, it is necessary to be acquainted with that science.

“ It may easily be demonstrated that there is an advantage in learning, both for the usefulness and the pleasure of it. There is something positively agreeable to all men, to all at least whose nature is not most grovelling and base, in gaining knowledge for its own sake.

“ When you see anything for the first time you at once derive some gratification from the sight being new ; your attention is awakened, and you desire to know more about it. If it be a piece of workmanship — as an instrument, a machine of any kind — you wish to know how it is made, how it works, and of what use it is. If it be an animal you wish to know where it comes from, how it lives, what are its dispositions, and generally its nature and habits.

“You feel this desire, too, without at all considering whether the machine or animal will ever be of the least

A practical use to you. But you have a curiosity to know all about them because they are new and unknown.

“ You accordingly make inquiries ; you feel a gratification in getting answers to your questions — that is, in receiv ing information and in knowing more ; you feel that you are better informed than you were before.

“ When you see another instrument or animal in some respects like it, but differing in other particulars, you find it pleasing to compare them together, to note where they agree and where they differ.

“ Now, all this kind of gratification is of a pure and disinterested nature, and has no reference to any of the common purposes of life, yet it is a pleasure, an enjoyment.

“You are nothing the richer for it, you do not gratify your palate or any other bodily appetite, and yet it is so pleasing that you would give something out of your pocket to obtain it and forego some bodily enjoyment for its sake.” 1

The truth of these words is well demonstrated by the enthusiasm which marks each devotee to science whatever his particular branch may be ; whether it is a profession or a pastime it is with him a delight.

But in all these vast realms it seems, to me at least, that the branch which possesses the greatest charm is that which deals with living forms.

Here we see the physical forces — chemistry, etc.- operating not only in modes that we are acquainted with, but in such ways as to present to us the most stupendous of problems — Consciousness.

We note the dawn of this in the simplest protoplasmic speck — this responding to stimulus. We note its advance as complexity of structure advances, up to its culminating point in ourselves.

Then living forms present us with the interesting points of structure in relation to environment. We note how

1 “ Circle of the Sciences.”

INTRODUCTORY

“ Each fashion of life, with reflex forcible action,

Works on the form.” 1

Then we have the enthralling study of development, which shows us that forms which in their adult state appear far as the poles asunder are yet closely related.

But I have not the inclination, even had I the ability, to enter into these deeper depths of the science. This has been, and is being, done by abler hands. The task I am setting myself is a survey of a small portion of Nature’s great domain — the natural history of our shores.

The “ great wide sea,” with its “ creeping things innumerable,” has always had a special fascination for me. Among its denizens we can most readily study the life cycle, and see the advance from the simple to the complex to the highest advantage.

Moreover, the sea is, upon very good grounds, held to be the birthplace of life : “ The nascent goal, from which the drama springs.”

But to soar a little less loftily, and come at once to the level of my subject, let me ask : Who is there that does not love the sea-sliore ; love to wander over shell-strewn sands and weed-draped rocks ; to peep into crystal rock pools, where the vegetation is crimson and scarlet, chocolate and emerald ? The plants rootless, leafless, and fiowerless, but in beauty of form and in delicate tracery outrivalling the choicest products of our hothouses.

Strange little worlds these rock pools, with some animals that look like flowers, and vie in form and colour with the brightest of these, and others that are living miniatures of the dragons of mythology.

There is a charm in this that appeals to all, from the romping school child to the grey-bearded professor.

And yet to how few are the wonders of the shore revealed ! I think I am safe in saying that, to three-fourths

1 Goethe.

of its visitors, it is just what a well-appointed library would be to a lad who has not learned to read. Such lad would find pleasure in a survey of the bright colourings and gilded bindings, but to him the glories that lie within the close-packed pages would have no existence.

My object in writing this little book is to help to open some of the volumes in this part of Nature's library, to assist in deciphering the text, and to point out, as far as I am able, the more readily understood passages.

Therefore to those who, while not prepared to “ give up, in short, both business and sport, and give themselves up tout entier to philosophy,1’ as did Sir Robert the Good, but who none the less would wish to gain an insight into the life histories, the place in Nature, and the ways and doings of some of the myriad forms that live upon our shores, I venture to address the chapters that follow.

It is only a few forms among these myriads that can be dealt with within the limits of this book, but I trust to be able to say sufficient to create an interest in the subject, and that my effort may prove a stepping-stone to the high-class monographs, each dealing with a particular section, that exist.

A learned writer has recentlv said that, to the naturalist of old, living things were objects to be collected, named, and classified, while to the modern one they are things to be studied and explained.

If this definition of each is complete, then I think that both ancient and modern fall short of completeness, and, holding that the thing studied and explained should also be collected and classified, I shall devote a not inconsiderable portion of my book to the matter of collection and preservation.

For, even apart from their scientific value, well-preserved specimens form interesting mementoes of days spent on the sea-shore.

INTRODUCTORY

In nomenclature, when more than one name has been applied to the same organism, I shall employ the one most generally in use, although recent revision may have made alteration ; and as to classification, I shall simply proceed from the lower to the higher groups, for the subject of strict classification is still somewhat unsettled — some authorities placing as one division, or even as one group, what others consider a subdivision of another.

For the details of the subject of classification I shall refer the reader to The Encyclopedia Britannica, where the different systems are given in full.

1 am writing this on the coast of Jersey, in the Channel Islands, a district proverbially rich in the variety of its marine fauna, although, as far as 1 can judge, there are very few forms that occur here that do not also occur on the shores of Great Britain in general — the reputation that these islands hold in this respect being simply due to the fact that many diverse geological conditions, each with its accompanying forms of life, are here concentrated into a limited area.

Before me, as I write, stretches the Bay of St Clement, a locality which has been my chief hunting-ground for nearly twoscore years. It is composed as follows

First a stretch of fine white sand ; then a large expanse of low-lying rocks, plentifully interspersed with rock pools, both deep and shallow ; stretches of loose shelly sand ; patches, many acres in extent, of Zostera or “ sea-grass ” ; and clusters of tall rocks, with their bases densely clothed with Fucus and Laminaria ; fallen blocks of stone, here and there bridge dykes and gullies, forming small caves and grottoes — the whole affording, as I have said, a great variety of conditions within easy reach of one another.

It may or may not be the good fortune of my young reader to light upon a similar shore on his next seaside visit, but, of course, one or more of the conditions named will be present, and will have its characteristic inhabitants, unless, indeed, he falls on evil times, and lights on a shore of rolling shingle, for such does not favour much in the way of zoology.

That mv voung reader has some bent in this direction I take for granted by the fact of his having this book in hand. Let me urge upon him to take up the subject as seriously as circumstances will allow, and I can promise that even a very elementary study of the living forms of our shores will open for him a fount of pleasure — of pleasure that does not pall.

The equipment required is, with perhaps the exception of a microscope, of the most simple and inexpensive kind. Hints on this will be given further on.

Chapter I The Protozoa

These are the simplest forms of animal life, each individual consisting of one cell only, a simple speck of that compound which Professor Huxley termed “ the Physical basis of life ” — Protoplasm.

A great number of forms live in fresh water — e.g. the so-called animalcules of stagnant pools — but many are marine. Among these is one of comparatively large size easily visible to the unaided eye. It is a globe-shaped organism, transparent as the water in which it lives, with a threadlike process serving as organ of locomotion, termed a flagellum. This is Noctiluca miliaris. In some parts of our seas it swarms. As its generic name (= Night-light) implies, it is luminous, and contributes in a large measure to the phenomenon of phosphorescence of the sea.

One division of the marine protozoa, termed the Rhizopoda , secrete shells either of silica or of carbonate of lime, always of very beautiful patterns. This division embraces two orders, Radiolaria and Foraminifera. The former, also known as Polycistina, has shells of silica, the Foraminifera, as a rule, shells of carbonate of lime. As the latter are the more conspicuous, and the most easily obtained and studied, we shall restrict ourselves to these, repairing to a sandy shore for our observations.

The stretch of sand before us, the tide having receded, and the sun partially dried its surface, is seen to present different shades of colour, the whitey- brown tint of quartz

Fig. 1

1 . Lagena vulgaris.

2. Lagena gracilis.

3. Lagena clavata.

4. Var. of Lagena gracilis.

5. Lagena striata.

0. Lagena striata interupta.

7. Lagena striata substriata.

8. Lagena vulgaris seniistriata.

9. Nodosaria radicula.

10. Nodosaria radicula , var.

1 1 . Dentalina subarcuata.

12. Spiroloculina depressa.

13. Spiroloculina depressa , var.

14. Miliolina seminulum.

15. Miliolina seminulum , var.

10. Miliolina seminulum, var.

17. Miliolina seminulum, under side.

IS. Miliolina bicornis.

19. Spiroculina depressa, var. rotunda.

20. Noneonina elegans.

21. Noneonina Barleeana.

22. Polystomella incerta.

23. Polystomella crispa.

24. Polystomella umbilicata.

25. Plencroplis planatus.

20. Nummulina p/anu/a.

27. Patelina corrugata.

28. Noneonina umbilicatula.

29. Spirit inn margaretifera.

30. Cristallaria calcar.

31. Bulimina pupaoides.

32. Planorbulina vulgaris.

33. Bulimina pupaoides, var. margmata.

34. Bulimina pupaoides, var. spinnlata.

35. Textularia difforinis.

36. Textularia rariabilis.

37. Textularia spathulata.

38. Bulimina pupaoides, var.

*

Fig. 1. — Various British Foraminifera and felspathic sand being here and there marked with patches, some nearly white, others almost black, the result of materials of different specific gravities having been now borne up, now deposited, by currents of air or water, chiefly by the latter.

The dark patches we can dismiss with a short shrift. They are smudges on Nature’s fair face made by the hand of man — fine cinder washed in from afar, where some steamer has cast overboard the contents of its ash-pit (unless we are on a shore where titanic iron sand occurs).

The white patches are the object of our quest. A pinch of their constituents examined with a good pocket lens reveals the fact that they are chiefly composed of shells —shells so minute that an ounce by weight will contain some millions of them ; and not only are they interesting, for a history attaches to them, but they are things of most exquisite beauty.

The Plate No. 1 will give an idea of what some of them are like. Among them are miniatures of ancient “ Lachrymal vases,” soda-water bottles, and cut-glass decanters. Some are like fossil ammonites, others like the productions of some very artistically inclined confectioner. They are in endless variety, and all are girded with beauty. Fig. 2 shows a photograph from nature of few forms.

But these are only the dead shells ; the living members of the tribe are farther afield — some are out on the ocean, many at its surface, others thousands of fathoms down. There are many in the mud and in the rock pools close at hand. But meanwhile let us collect some of these dead ones.

There are several methods of attaining this end. The best one, 1 find, is to lay a piece of paper — say a newspaper —close to a white patch, and then, with something that will create a stiff! sh current of air — a lady’s fan would be the thing, par excellence, if such could be obtained — waft the

THE PROTOZOA lightest portion on to the paper, then collect, and pour into any suitable receptacle.

The surface of the sand may also be scraped to the same end, but this plan takes up an unnecessary quantity of sand.

The gathering when brought home must be thoroughly

Fig. 2. — Mixed Foraminifera. Photo-micrograph — about 20 diameters

dried on the stove or before the fire, and then when quite cold, not before, it must be tipped, a spoonful at a time, into a basin of cold water, and well stirred with the spoon. The stirring must be considerable, or little bells of air will adhere to sand grains, and cause these to float as well as the little hollow shells we desire. However, the sand will sink and the air-charged shells will float. Now collect and dry these treasures, and put them aside for further manipulation and for microscopic mounting — methods for doing which will be given in the proper place.

Of course, for the appreciation of this particular branch of zoology a microscope is needed, but to the young reader, interested even thus far, the possession of this engine of science cannot be a remote event

Now who are, or rather who were, in the case of the dead ones, the dwellers in these shells ?

Firstly, the name Foraminifera changed into familiar English is “ door-bearers,” and the name is given them, because all, or nearly all, the little shells are perforated with minute holes, through which the inmate can protrude long threads of his substance ; for his is not of “ muscle and nerve miraculously spun,” but is, as we have seen, a speck of the glairy white of - egg - looking substance — protoplasm.

And this is how he dines. A morsel suitable for a meal being within reach, some of the threads are extended, and coalesce into a blob. This envelops the morsel, digests and assimilates the good portion, and rejects the remainder. Then, enriched by the meal, the foraminifer withdraws its substance into the shell.

These semi-fluid threads also serve the purpose of locomotion ; hence they are termed Pseudopodia ( ‘ k false feet ”), and by their extension in one direction and their withdrawal in the other the little animal proceeds.

When an individual has reached size limit some of the extruded protoplasm breaks off, secretes lime from its solution in the sea- water, and becomes a new individual. Thus they multiply.

In speaking of the contents of the cell as a u simple ' speck, I say so guardedly, for a living cell is more complex than was formerly supposed, of which more anon.

I said just now that the Foraminifera had a history

THE PROTOZOA attached to them, and so they have. 1 hey are, or are believed to be, the oldest of animal forms *, that time was when they were the sole inhabitants of this earth.

(Minute vegetable forms must, however, have preceded them, as the chief distinction between vegetable and animal life is that the former can manufacture protein compounds from the raw elements of earth, while the latter must obtain these already prepared by the action of some other living form.)

And surely enough, in the Laurentian rocks of Canada, the oldest page in Mother Earth’s diary that has mention of living things at all, there are records of them, and they must even then have existed in such numbers that their shells have formed vast rocky reefs.

To these early fossil ones geologists have given the name Eozoon — the “ dawn of life animal.”

Then in the ages that have followed they have lived and died in such quantity that it is mostly of their remains that our chalk hills are built, in some places thousands of feet in thickness.

It is also to the existence of these little animals that England owes its classical name — Albion, “ the white land ” — a title bestowed upon it two thousand years ago by the Gauls, who could see its Foraminifera- built cliffs across the Channel.

To see some of the living forms we have choice of two methods. If a deposit of mud from low down in tide range is available, place some of it in a wide-mouthed jam jar with sea- water, shake up well, and then pour off the fine portion. (This is a reversal of the process we employed in getting the dead shells.) The living “ forams ” are heavier than the mud, and will sink ; by repeated washings the water will be clear, and only the clean, gritty particles that were among the mud will remain. Now fill the jar with clean, clear water, and set it aside. In the course of a few hours some of the little creatures will have crawled up the sides of the jar, and can be observed, by means of a pocket lens, extruding and retracting their pseudopodia. They can then be transferred to a slip or to a “ Zoophyte trough,” and studied under the microscope.

If no mud is available take a few handfuls of sea-weed preferably coralline — from a rock pool, wash them in the jar, remove the larger scraps, and save the deposit as in the previous case.

It will be noticed that the ammonite and other whorled shelled forams extrude their pseudopodia from the little holes on all sides, but that some forms — Miliolina , Laqena, etc. (see Fig. 3) — extrude them by one opening.

Allusion to some of the other protozoa will be made in the chapter on collecting.

CHAPTER IJ

The next division of the animal kingdom in the ascending scale is represented by the sponges. Here complexity commences, but “ tissues,” as regards muscle, etc., are not yet apparent, although foreshadowed. Some naturalists do not admit the sponges as a group or Phylum by themselves, but include them in the next — viz. in the Ccelenterata— but the majority seem to be in favour of keeping them separate

The text-books thus define the Porifera : Animals with soft bodies composed of a large number of cells, which cells have the power of amoeboid movement.

The structure is supported and maintained in form either by a skeleton of horny fibres, by spicules of carbonate of lime, or by spicules of silica.

The mass is pierced by a vast number of pores (hence Porifera , “ pore-bearing ”) opening into a series of canals, which communicate with little hollow chambers — digestive cavities — and each sponge has one or many k‘ exhalent apertures ” (osculce).

In adult life they are affixed and plantlike. In early life they are active, and free swimming. They have different methods of reproduction — viz. :

One by budding, by which means the mass extends laterally and in thickness, for except in a few species there is little precise form or size limit. They also reproduce by means of eggs, from which develop free-swimming embryos,

PORTFERA which lead a roving life for a brief period, and then settle down, and proceed to extend as above said.

I have observed in one species at least (it occurs in several others) another method of propagation. In Tethya lyncurium, at the end of summer, the surface becomes covered with little protuberances, which at length become

Fig. 4. — Tethya lyncurium budding, natural size. Inset, a freed bud enlarged about 6 times

stalked and furnished with a radiating arrangement of spicules ; then these break away, and are carried by currents to other localities, where they affix and grow to the form of the parent.