A manual of elementary geology: or, The ancient changes of the earth and its inhabitants, as illustrated by geological monuments

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Preface

TO

THE FOUETH EDITION.

In consequeDce of the rapid sale of the third edition of the " Manual/* of which 2000 copies were printed in January last, a new edition has been called for in less than a twelvemonth. Even in Uiis short interval some new facts of unusual importance in pakeontology have come to light, or have been verified for the first time. Instead of introducing these new discoveries into the body of the work, which would render them inaccessible to the purchasers of the former edition, I have given them in a postscript to this Preface (printed and sold separately), and have pointed out at the same time their bearing on certain questions of the highest theoretical interest*

As on former occasions, I shall take this opportunity of stating that the " Manual " is not an epitome of the " Principles of Geology," nor intended as introductory to that work. So much confusion has arisen on this subject, that it is desirable to explain fully the different ground occupied, by the two publications. The first five editions of the " Principles " comprised a 4th book, in which some account was given of systematic geology, and in which the principal rocks composing the earth's crust and their organic, remains were described. In subsequent editions this book was omitted, it having been expanded, in 1838, into a separate treatise called the ** Ellements of Geology," first re-edited in 1842, and again recast and enlarged in 1851, and entitled "A Manual of Elementary Geology."

Although the subjects of both treatises relate to geology, as their titles imply, their scope is very different ; the " Principles " containing a view of the modem changes of the earth and its inhabitants, while the *' Manual ** relates to the monuments of ancient changes. In separating the one from tlie other, I have endeavoured to render each complete in itself^ and independent ; but if asked by a student which be should read first, I would recommend him to begin with the "Principles,** as he may then proceed from the known to the unknown, and be provided beforehand with a key for interpreting the ancient phenomena, whether of the organic or inorganic world, by reference to changes now in progress.

* Postscript to 4th edition of the Manual, price 6d

A S

Tl PREFACE.

Owing to the former incorporation of the two subjects in one work, and the supposed identity of their subject matter, it may be useful to give here a brief abstract of the contents of the " Principles," for the sake of comparison.

Abstract of the " Principles of Geology,^ Eighth Edition,

Book I

1. Historical sketch of the early progress of geology, chaps, i to ir.

2. Circumstances which combined to make the first cultivators of the science regard

the former course of nature as different from the present, and the former changes of the earth's surface as the effects of agents different in kind and degree from those now acting, chap. v.

8. Whether the former variations in climate established bj geology are explicable

by reference to existing causes, chaps. vL to viiL

4. Theory of the progressive development of organic life in former ages, and the

introduction of man into the earth, chap. ix.

5. Supposed former intensity of aqueous and igneous causes considered, chaps, x.

and xi

6. How far the older rocks differ in texture from those now forming, chap. xii.

7. Supposed alternate periods of repose and disorder, chap, xiiu

Book II. CHAH0B8 NOW IN FROOBE8S IN THE INORGANIC WORLD

b. Aqueous causes now in action : Floods — Rivers — Carrying power of ice — Springs and their deposits — Deltas — Waste of cliffs and strata produced by marine currents : chaps, xiv. to xxii.

9. Permanent effects of igneous causes now in operation': Active Yokanos and

earthquakes — their effects and causes : chaps, xziii. to xxxiiL

Book HI.

CHAN0E8 OF THE ORGANIC WORLD NOW IN PROGRESS.

10. Doctrine of the transmutation of species controverted, chaps, xxxiv. and xxxv.

1 1. Whether species have a real existence in nature, chaps. xxxvL and xxxviL

12. Laws which regulate the geographical distribution of species, chaps, xxxvlii.

to xl.

13. Creation and extinction of species, chaps, xli. to xliv.

14. Imbedding of organic bodies, including the remains of man and his works, in strata now forming, chaps, xlv. to 1.

15. Formation of coral reefs, chap. IL

It will be seen on comparing this analysis of the contents of the " Principles'* with the headings of the chapters of the present work (see p. xxiii.), that the two treatises have but little in common ; or, to repeat what I have said in the Preface to the 8th edition of the "Principles," they have the same kind of connection which Chemistry bears to Natural Philosophy, each being subsidiary to the other, and yet admitting of being considered as different departments of science.*

Charles Lyell.

11 Harl^ Street, London^ December 10. 1851.

* As it is impossible to enable the reader to recognise rocks and minerals at sigfat by aid of verbal descriptions or figures, he will do well to obtain a well-arranged collection of specimens, such as may be procured from Mr. Tennant (149. Strand), teacher of Mineralogy at King's College, London.

POSTSCRIPT.

Tracks of a Lower Silurian reptile in Canada — Chelonian footprints in 'Old Red Sandstone, Morayshire — Skeleton of a reptile in the same formation in Scotland — Eggs of Batrachians (?) in a lower cUvision of the " Old lied,** or Deronian — Footprints of Lower Carboniferous reptiles in the United States — Fossil run-marks of the Carboniferous period in Nova Scotia — Triassic Mammifer from the Keuper of Stuttgart — Cretaceous Gasteropoda — Dicotyledonous leaves in Lower Cretaceous strata — Bearing of the recent discoveries above-mentioned on the theory of the progressive development of animal life.

Tracks of a Lower Silurian reptile in Canada. — In the year 1847, Mr. Robert Abraham announced in the Montreal Grazette, of which he was editor, that the track of a freshwater tortoise had been observed on the surface of a stratum of sandstone in a quarry opened on the banks of the St. Lawrence at Beauhamais in Upper Canada. The inhabitants of the parish being perfectly familiar with the track of the amphibious mud-turtles or terrapins of their country, assured Mr. Abraham that the fossil impressions closely resembled those left by the recent species on sand or mud. Having satisfied himself of the truth of their report, he was struck with the novelty and geological interest of the phenomenon. Imagining the rock to be the lowest member of the old red sandstone, he was aware that no traces had as yet been found of a reptile in strata of such high antiquity.

He was soon informed by Mr. Logan, at that time engaged in the geological survey of Canada, that the white sandstone above Montreal was really much older than the *' Old Red," or Devonian. It had in fact been ascertained many years before, by the State surveyors of New York (who called it the " Potsdam Sandstone "), to lie at the base of the whole Silurian series. As such it had been pointed out to me in 1841, in the valley of the Mohawk, by Mr. James Hall*, and its position was correctly described by Mr. Emmons, on the borders of Lake Champlain, where I examined it in 1842. It has there the character of a shallow-water deposit, ripple-marked throughout a considerable thickness, and full of a species of Lingula. The flat valves of this shell, of a dark colour, are so numerous, and so arranged in horizontal layers, as to play the part of mica, causing the rock to divide into laminae, as in some micaceous sandstones.

When I mentioned this rock in my Travels f as occurring between Kingston and Montreal, (the same in which the Chelonian foot-prints have since been found,) I spoke of it as the lowest member of the Lower Silurian series ; but no traces of any organic being of a higher grade than the Lingula had then been seen in it,

* Travels in North America by the Author, vol. iL chap. 22. j Ibid. 1842.

A 4

Vlll LOWEB SILURIAN BEPTILE.

and I called attention to the singular fact, that the oldest fossil form then known in the worlds was a marine shell strictly referable to a genus now existing.

Early in the year 1851, Mr. Logan laid before the Greological Society of London a slab of this sandstone from Beauharnais, containing no less than twenty-eight foot-prints of the fore and hind feet of a quadruped, and six casts in plaster of Paris, exhibiting a continuation of the same trail. Each cast contained from twenty-six to twenty-eight impressions with a median channel equidistant from the two parallel rows of foot-prints, the one made by the feet of the right side, the other by those of the left. In these specimens a greater number of successive foot-marks belonging to one and the same series were displayed than had ever before been observed in any rock ancient or modem. Mr. Abraham has inferred that the breadth of the quadruped was from five to seven inches. A detailed account of the trail was published by Professor Owen, in April 1851, from which the following extracts are made.

" The foot-prints are in pairs, and the pairs extend in two parallel series, with a channel exactly midway between the right and left series. The pairs of the same side succeed each other at intervals, varying from one inch and a half to two inches and a half, the common distance being about two inches. The interval between the right and left pairs, measured from the inner border of the small prints, is three inches and a half, and from the outer border of the exterior or large prints, is seven inches. The shallow median track is one inch and a quarter in breadth, varying in depth, but not in its relative position to the right and left foot prints."

" The inference to be deduced from these characters is, that the impressions were made by a quadruped with the hind feet larger and somewhat wider apart than the fore feet, with both hind and fore feet either very short, or prevented by some other part of the animal's structure from making long steps ; and with the limbs of the right side wide apart from those of the left ; consequently, that the quadruped had a broad trunk in proportion to its length, supported on limbs either short, or capable only of short steps, and with rounded and stumpy feet, not provided with long claws. There are faint traces of a fine reticulate pattern of the cuticle of the sole at the bottom of some of the foot-prints on one portion of the sandstone ; and the surface of the sand is generally smoother there than where not impressed, which, with the rising of the sand at the border of the prints, indicates the weight of the impressing body. The median groove may be interpreted as due either to the abdomen or the tail of the animal ; but as there is no indication of any bending or movement of a tail from side to side, it was probably scooped out of the goft sand by a hard breast-plate or plastron. If this were so, it may be inferred that the species was a fresh-water or estuary tortoise rather than a land tortoise." *

Previously to this ' discovery, the trias was the oldest stratum in

* Quart, Journ. Geol. Soc. 1 851, vol. Yii. p. 250.

BEFTILES IV OLD BED SANDSTONE. ix

which txiy remsiins or signs of a Chelonian had been detected. Numerous other trails Lave aince been observed (1850-51) in various localities in Caooda, all in the same very ancient fossiliferous rock -, and Hr. Logan, who baa visited the spots, will shortl; publish a description of the phenomena.

Cheloman foot-prinU m Old Red Sandttone, Morayshire. — Captain Lambart Brickenden^ has just communicated to the Geological Society of London a drawing and description of a continuous ■eries of no less than thirty-four foot-prints of a quadruped observed in the course of last year (1850), on a slab of sandstone quarried at Cummingatone, near Elgin, in Morayshire, a rock which has always been considered as an upper member of the Devonian or " Old Ked," • A part of the track, the course of which was from a to b, is repre-

■ er

Bented in the annexed woodcut, fig. 521. The foot-prints ore in pairs, forming two parallel rows, which are somewhat less distant from each other than those of the Lower Silurian tortoise of Canada above mentioned. The stride, on the other hand, ia four inches, or twice that of the Beauhamais Chelonian. The hind foot is exactly of the same size, being one inch in diameter, and larger than the fore foot in the proportion of four to three.

Skeleton of a reptile, allied to the Batraehiani, in the Old Bed Sandstone of Morayshire. — Mr. Patrick DufiT, author of a " Sketch of the Geology of Morayshire " (Elgin, 1842), obtained recently (October, 1851), from the rock above alluded to, the first example ever seen of the skeleton of a reptile in the Old Red Sandstone. He has kindly allowed me to give a figure of this fossil, of which Dr. Mantell has drawn up a detailed osteologicnl account for publication in the " Journal of the Geological Society of London." The bones in this specimen have decomposed, but the natural position of almost all of them can be seen, and nearly perfect casts of their form taken from the hollow moulds which they have left.

■ The fenenllf received delerminatian of the »f^ al this rock ii proluhly correct ; hut u there we no oTerlying coal-mesiurej end no trell-known Deioniin CmhU in the vhitUh itme of Elgin, and ei I have not penonally eiplurerl the INoloKT of that dUtrict, 1 canaot ipL-ak ai confident); as in regard to the age of the M«atreal Cbelonian.

Z BEPTILE IN OLD RED EAKDSTONE.

The mntrix is a fine-grained, whitish sandstone, with a cement of carbonate of lime. The skeleton exhibits the general characters of the Lacertians, blended with peculiarities that are Batrachian. Hence Dr. Mantell infers that this reptile was either a freshwater Batrachian, resembling the Triton, or a smaU terrestrial Lizard. Slight indications are visible of Fif.ssj. ver^ minute conical teeth. Cap-

tain Brickenden, who is well acquainted with the geok^y of that part of Scotland, informs me that this fossil was found in the Hill of Sp^nie, north of the town of Elgin, in B rock quarried for building, and the same in which the Chelonian foot-prints, alluded to in the last page, occur. The skeleton is about four and a half inches in length, but part of the tail is concealed in the rock. Dr. Mantell has proposed for it the generic name of Telerpeton, from nfXt, afar off, and IpTrtTov, a reptile ; while the specific name Elginense commemorates the principal place near which it was obtained.

Effffs of Balrachiaru (?) tn the Old Red Sandstone of Scotland. — At page 344. of this work I have given two figures (figs. 397 and 398.) of small groups of eggs, very common in the shales and sandstones of the "Old Red" of Kincardineshire, Forfarshire, and Fife.

I threw out as a conjecture, that they might belong to gastero- N.iunitiw. ^^yg moUusca, like those repre-

.^»T» S'ri,LT~ ». -eaiea in «B. 399. p. 3*5. i bat Dr. Dim. Monrthire. Mantel], somc years ago, sliowed

me a small bundle of the driedup eggs of the common English frog (see fig. 524 a.), black and carbonaceous, and BO identical in appearance with the fossils in question, that he suggested tlie probability of these last being of Batrachian origin. The plants by which they are often accompanied (fig. 398. p. 344.), I formerly supposed to be Fuci, but Sfr. Bunbury tells me that their grass-like form threes well with the idea of their being freshwater, and of the family Fluviales.

The absence of all shells, so far as our researches have yet gone, in the slates and sandstones of Scotland above alluded to, raises a presumption against their marine origin, and a still stronger one against the fossil eggs being those of Gasteropoda. It is well known

BATBACHUN EQGS IN "OLD BED.** xi

that a single female of the Bfttrachian tribe qects annuallj an astoniahing qoantitj of spawn. Mr. Newport, author of many accurate researches into the metamorphoses of the Amphibia, having examined my fossils from Forfarshire, concurs in Dr. Mantell's opinion that the clusters of eggs (flgs. 897. 898. p. 344.) may be thoM of frogs ; while other larger ones, occurring singly or in piurs in the same alatea, and often attached to a leaf, may be the ova of a gigantic Triton or Salamander. (See flgs. 523, 524, 52fi.) I may observe that the subdivision of the Old Bed Sandstone, in which these plante and ova occur (No. 4. of the section, fig. 62, p. 48.), is considerably lower in position than the rock in which the Telerpeton of Elgin is imbedded.

Foot-pritUt of Lower Carboniferotu reptiles in the Uniled Slatet. — 1 have stated, at p. 340., that in 1849, Mr. Isaac Lea observed the foot-marks of a large reptile in the lowest beds of the coal formation at Poltsville, about seventy miles N. £. of Philadelphia. These researches have since been carried farther by Frofessor H. D. Sogers, in the same region of anthracitic coal, lying on the eastern flank of the Alleghany Mountains. Beneath the productive coal-measures of that country occurs a dense moss of red shales and sandatones, which correspond nearly in position to the millstone grit and HoQUtoin Limestone of the south-east of England. In these beds foot-prints, referred to three species of quadrupeds, have lately been detected, all of them five-toed and in double rows, with an opposite symmetiy, as if made by right and left feet, while they likewise display the alternation of fore foot and hind foot. One species, the largest of the three, presents a diameter for each foot-print of about two inches, and shows the fore and hind feet to be nearly equal in dimensions. It exhibits a length of stride of about nine inches, and a breadth between the right and left treads of nearly four iacbe*. The impressions of the hind feet are but little in the rear of

Xll BAIN-PBINTS IN COAL SHALE,

the fore feet. The animal which made them is supposed to have been allied to a Saurian, rather than to a Batrachion or Chelonian ; but more iaformatioa is required before so difficult a point can be decided. With these foot-marks were seen Bhrinkage cracks, such as are caused by the sun's heat in mud, and rain-spots, with the signs of the trickling of water on a wet, sandy beach ; all confirming the conclusion derived from the foot-prints, that the quadrupeds belonged to air-breathers, and not to aquatic races," The Cheirotherian footprints, figured hy me at p. 338., in which the fore and hind feet are very unequal in size, betoken a distinct genus, and occur in the midst of the productive coal measures, being consequently less ancient

On FomU Rain-markM of the Carboniferous Period in North America. — Having alluded to the spots left by rain on the surface of carboniferous strata in the Alleghanies, on which quadrupedal footprints are seen, I may mention that similar rain-prints are conspicuous in the coal measures of Cape Breton, in Nova Scotia, in which Mr. Richard Brown has described Stigmarite and erect trunks of trees, and where there are proofs, as stated at p. 324., of many fossil forests ranged one above the other. In such a region, if anywhere, might we expect to detect evidence of the fall of rdn on a sea-beach. 90 repeatedly must the conditions of the same area have oscillated between land and sea. The intercalation of deposits, containing shells of marine or brackish water, indicate the constant proximity of a body of salt water when the clays which supported the upright trees were formed. In the course of 1851, Mr. Brown had the kindness to send me some greenish slates from Sydney, Cape Breton, on which are impnuted very delicate impressions of rain-drops, with several worm-tracks (a, b, fig. 526.), such as usually accompany rain> marks on the recent mud of the Bay of Fundy, and other modem beaches, t

Fi» see. Hi. sa.

Fig. sa. Cutmnlfc

T]g.sin. Cuu

FOSSIL MAUHirER IN TRIAS.

The casta of rain-prints, ia figs. 627. and £28., project from the under side of two lajers, occurring at different lerels, the one a Miidj shale, resting on the green shale (fig. 526.), the other a sandstone presenting a similar wartj or blistered surface, on which are also observable some small ridges as at a, which stand ont in relief, and afford evidence of cracks formed by the shrinkage of subjacent clay, on which rain had fallen. Many of the associated sandstones are described by Mr. Brown as ripple- marked.

The great humidity of the climate of the coal period had been pre- Tioasly inferred from the nature of its vegetation and the continuity of its forests for hundreds of miles ; but it is satisfactory to have at length obtained such positive proofs of showers of rain, the drops of which resembled in their average size those which now fall from the clouds. From such data we may presume that the atmosphere of the carboniferous period corresponded in density with that now investing the globe, and that different currents of air varied then as now, in temperature, so as to give rise, by their mixture, to the condensation of aqueous vapoiu:.

Triaaiie MammiftT {Sficrolestet antiquut Plieninger.) — In the year 1847, Professor Plieninger, of Stuttgart, published a description of two fossil DH^ar teeth, referred by him to a warm-blooded quadruped*, which he obtained from a bone-breccia in Wiirtembeig occurring between the has and the keuper. As the aunonnoement of so novel a fact has never met with the attention it deserved, we are indebted to Dr. Jager, of Stuttgart, for having recently reminded us of it in his Memoir on the FossU Mammalia of "fffirtemberg.f

Fig. 529. represents the tooth first found, taken from the plate published in 1847, by Professor Plieninger ; and fig. 530. is a drawing of the same executed from the original by Mr. Hermann von Meyer,

■ Wiirtembergueh. Nituntiuen JthrnheAe. 3 Jahr. Stultgart, 1847. t No*. Act. And. Csnr. Leopold. NiL Cur. 1S50, p. 90S. For figures, see ibirf. plate iiL Bgi. 14, 15, IS, IT.

Xir FOSSIL KAMMIFEB IK TBIA8.

which he has been kind enough to send me. Fig. 629. is a second and larger molar, copied from Dr. Jager*s plate Ixxi., fig. 16.

J

MicroUstet antfqvut^ Plienlngrr. Molar tooth magnified. U|)per Triai. Diegerloch, near Stuttgart, Wurtemberg.

a. View of inner side ? e. Same in profile.

b. same, outer side ? dl Crown or aame.

I

Wer6U$U* antiqmut Plien.

View of same molar as No. 589. From a drawing hj Hernum von Meyer

a. View of inner

side?

b. Crown of lame:

Fig. 531. Professor Plieninger inferred in 1847, from the

double fangs of this tooth and their unequal size, and

from the form and number of the protuberances or

cusps on the flat crowns, that it was the molar of a

Mammifer ; and considering it as predaceous, probably

insectivorous, he called it Microlestes, from /icKpoc,

little, and Xiyorijc, a beast of prey. Soon afterwards,

usf Plien. 4 times he found the second tooth also, at the same locality,

Ss.^'f rora Sfe Diogerloch, about two miles to the south-east of Stutt-

£ch. stutSS!'" gart. Some of its cusps are broken, but there seem to

have been six of them originally. From its agreement in general

characters, it is supposed by Professor Plieninger to be referable

to the same animal, but as it is four times as big, it may perhaps

have belonged to another allied species. This molar is attached to

the matrix consisting of sandstone, whereas the tooth. No. 529., is

isolated. Several fragments of bone, differing in structure from that

of the associated saurians and fish, and believed to be mammiferous,

were imbedded near them in the same rock.

Mr. Waterhouse, of the British Museum, after studying the annexed figs. 529. 531. and the descriptions of Prof. Plieninger, observes, that not only the double roots of the teeth and their crowns presenting several cusps, resemble those of Mammalia, but the cingulum also, or ridge surrounding the base of that part of the body of the tooth which was exposed or above the gum, is a character distinguishing them from fish and reptiles. "The arrangement of the six cusps or tubercles in two rows, in fig, 529., with a groove or depression between them and the oblong form of the tooth, lead him, he says, to regard it as a molar of the lower jaw. Both the teeth differ from those of the Stonesfield Mammalia*, but do not supply sufficient data for determining to what order they belonged. Even in regard to the Stonesfield jaws, where we possess so much ampler materials, we cannot safely pronounce on the order."

* See Manual, p. 268.

SPIRAL UNIYALYES IN CHALK. XT

Professor Plieninger has sent me a cast of the smaller tooth, which exhibits well the characteristic mammalian test, the double fang ; but Mr. Owen, to whom I have shown it, is not able to recognize its affinity with any mammalian type, recent or extinct, known to him.

It has already been stated that the stratum in which the above-mentioned fossils occur is intermediate between the lias and the uppermost member of the trias. That it is really triassic may be deduced from the following considerations. In Wiirtemberg there are two ** bone-beds," one of great extent, and very rich in the remains of fish and reptiles, which intervenes between the muschelkalk and keuper, the other, containing the Microlestes, less extensive and fossiliferous, which rests on the keuper, or superior member of the trias, and is covered by the sandstone of the lias. The last-mentioned breccia therefore occupies the same place as the well-known English '* bone-bed" of Axmouth and Aust-cliff near Bristol, which is shown * to include characteristic species of muschelkalk fish, of the genus Sauricthys, Hybodus, and Gyrolepis. In both the Wiirtemberg bone-beds these three genera are also found, and one of the species, Sauricthys Mougeotii, is common to both the lower and upper breccias, as is also a remarkable reptile called Nothosaurus mirabilis. The Saurian called Belodon by H. Von Meyer of the Thecodont family, is another Triassic form, associated at Diegerloch with Microlestes.

Previous to this discovery of Professor Plieninger, the most ancient of known fossil Mammalia were those of the Stonesfield slate, a subdivision of the Lower Oolite | no representative of this class having as yet been met with in the Fuller's earth, or inferior Oolite (see Table, p. 258.), nor in any member of the lias.

Thecodont Saurians, — This family of reptiles is common to the Trias and Permian groups in Germany, and the geologists employed in the government survey of Great Britain have come to the conclusion, that the rock containing the two species alluded to at p. 306., and of which the teeth are represented in figs. 348, 349., ought rather to be referred to the Trias than to the Permian group.

CRETACEOUS GASTEROPODA.

In Speaking of the chalk of Faxoe in Denmark (p. 210.) or the highest member of the Cretaceous series, I have remarked that it is characterised by univalve Mollusca, both spiral and patelliform, which are wanting or rare in the white chalk of Europe. This last statement requires, I find, some modification. It holds true in regard to certain forms, such as Cyprasa and Oliva, found at Faxoe ; but M. A. d'Orbigny enumerates 24 species of Gasteropoda from the white chalk (Terrain S^nonien) of France alone. The same author describes 134 French species of Gasteropoda from the chloritic chalk marl and npper greensand (Turonien), 77 from the gault, and 90 from the lower greensand (Neocomien), in all 325 species of Gasteropoda,

Xiy FOSSIL KAMHIFEB IK TBIA8.

which he has heen kind enough to send me. Fig. 629. is a second and larger molar, copied from Dr. Jager*8 plate Ixxi., fig. 15.

J

Microlettet ttntimau^ Plieningrr. Molar tooth magnified. U|)per Tria«, Diegerioch, near Stuttgart, Wurtemberg.

a. View of inner fide ?

b. same, outer tide ?

e. Same in profile. d. CrowD or same.

I

Mferoletia antiquust Plien.

View of same molar a« No. 529. From a drawing b^ Hernuui von Meyer

a. View of inner

side?

b. Crown of ume.

Fig. 531. Professor Plieninger inferred in 1847, from the

double fangs of this tooth and their unequal size, and from the form and number of the protuberances or cusps on the fiat crowns, that it was the molar of a Mammifer ; and considering it as predaceous, probably insectivorous, he called it Microlestes, from /iticpoc, , ,,. , little, and Xiyorryc, a beast of prey. Soon afterwards,

<M7Pi<en.4timec hc found the sccond tooth also, at the same locality, 589. ^Kora the Diegcrloch, about two miles to the south-east of StuttkSh, stuttJlS!'" gart. Some of its cusps are broken, but there seem to have been six of them originally. From its agreement in general characters, it is supposed by Professor Plieninger to be referable to the same animal, but as it is four times as big, it may perhaps have belonged to another allied species. This molar is attached to the matrix consisting of sandstone, whereas the tooth, No. 629., is isolated. Several fragments of bone, differing in structure from that of the associated saurian s and fish, and believed to be mammiferous, were imbedded near them in the same rock.