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oviparous quadrupeds that peopled the islands and continents in the earlier ages of the world, should consult Cuvier's "Ossemens Fossiles," and the works of later writers on the subject; especially those of Professor Owen on this branch of British Palæontology.

FOSSIL CROCODILE OF SWANAGE. (Goniopholis crasssidens.)1 Wall-case A.-Swanage is a little town on the east coast of the Isle of Purbeck, whose inhabitants carry on a brisk trade in the exportation of stone from the numerous quarries in the vicinity, there being a good bay and anchorage for vessels. The town stands at the mouth of the bay, about six miles E.S.E. of Corfe Castle. The coast presents a section of the Cretaceous and Wealden strata, from the Chalk to the Purbeck beds; the Portland oolite, on which the lowermost freshwater strata repose, appearing on the south. Remains of Turtles, and fishes of species peculiar to the Wealden formation, are often found; and occasionally bones and teeth of large saurians.2

parts described, from Dr. Grant's articulated skeleton, which is 16 feet in length. I have felt it necessary to append this note, as in a recent publication the importance of a knowledge of this fact to the comparative anatomist is put prominently forth, but without the slightest allusion to the original observer.

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LIGN. 37.-SACRUM AND FIRST CAUDAL VERTEBRA OF A GAVIAL. FROM A SKELETON, 16 FEET LONG, IN THE ANATOMICAL MUSEUM OF PROFESSOR ROBERT E. GRANT, UNIVERSITY COLLEGE.

(nat. size.)

1, 2. The SACRUM, consisting of two coalesced vertebræ.

3. The First Caudal Vertebra, having both the articular extremities convex.

1" Goniopholis, in reference to the rectangular form, size, number, and firm junction of the osseous scutes (poxides)."-Prof. Owen, British Association Reports, 1841.

2 See my "Geological Excursions round the Isle of Wight, and along the coast of Dorsetshire:" 2d Edit. p. 345.

In the summer of 1835, the workmen employed in a quarry near Swanage, on splitting asunder a large slab of Purbeck limestone, perceiving teeth and portions of bones exposed on the corresponding surfaces of the slabs they had separated, carefully preserved the two pieces of stone and, fortunately, my friend Robert Trotter, Esq., who was a visit in the neighbourhood, heard of the discovery, and purchased the specimens for me.

The slabs when first received by me gave but obscure indications of the remains that careful chiselling subsequently brought to light. After much labour, I succeeded in developing the detached parts of the skeleton now visible, and fortunately without fracturing the stone by which they were concealed; consequently, the two corresponding surfaces are in a beautiful state of preservation; and being placed together in the same case, may be examined with facility; they are now as interesting groups of Crocodilian remains as have been discovered in this country.

On the left-hand slab are seen the posterior parts of the left side of the lower jaw with two teeth attached, and several detached teeth distributed about the stone; there are many ribs; numerous amphicœlian, or biconcave vertebræ, having a small irregular medullary cavity in the centre of the body of the bone; slender chevron-bones, with a bifurcated or double process of attachment, as in the crocodile; the ischium, pubis, ilium, and other parts of the pelvic arch; and a few bones of the extremities.

The vertebræ, the largest of which are nearly two inches long, are fractured across the middle, at right angles to their articulations, so that in every instance the articular ends of the body are concealed; transverse vertical sections of the centrum, with the spinous process, and long straight transverse processes attached, are the only parts visible. (Lign. 38. 2, 2). But several nearly perfect vertebræ of the same type, collected from the strata of Tilgate Forest, show that the articular surfaces are very slightly concave, as is the case in almost all the crocodilian vertebræ of the secondary formations. The suture uniting the annular part of the vertebræ to the body is well defined; the sacral vertebræ are beautifully displayed.

With these are the remains of the dermal cuirass, consisting of numerous scutes or dermal bones, scattered at

random among the other detached parts of the skeleton. There are, likewise, numerous scales and teeth of a small ganoid fish (Lepidotus minor), of a species that is common in

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LIGN. 38.-FOSSIL REMAINS OF A CROCODILIAN REPTILE, FROM THE
WEALDEN DEPOSITS. SWANAGE, 1835.

(Goniopholis crassidens.)

(The original is 33 feet long, and 3 feet wide.)

Part of the left side of the lower jaw, with two teeth attached.
Detached vertebræ, fractured across, and showing vertical sections of the
centrum, or body.

1.

2.

3.

Dermal scutes-the smooth inner surface exposed.

3'.

showing the deeply sculptured external surface.

4.

Ribs, all imperfect.

5.

Chevron-bones, or hæmapophyses.

6, 6. The two pubic bones (Pubis).

7, 7. The two ischiac bones (Ischium.)

8, 8. Bones of the Pelvis; consisting of the coalesced sacral vertebræ, and the two iliac bones.

the Purbeck strata. In the small diagram, Lign. 38, outlines of the most important parts are given, and numbered, so as to admit of easy reference. On the opposite stone are seen

the corresponding portions of several of the bones, as well as others of which there are no traces, on the left-hand piece.1

Teeth of Goniopholis.-(Lign. 39.)-The teeth of this reptile are of the usual crocodilian type; they are cylindrical, and smooth at the base, and have a rounded obtusely conical enamelled crown, the surface of which is strongly marked by numerous well defined longitudinal grooves and ridges, with a prominent median ridge on each side, placed anteriorly and posteriorly. Teeth of this kind are not uncommon in the strata of Tilgate Forest, and other localities of the Weald of Sussex: they were described by me in 1822 ("Fossils of the South Downs," p. 50), and subsequently in the "Fossils of Tilgate Forest," (p. 64, Pl. V. figs. 1, 2, 3, 7): specimens which I transmitted to Baron Cuvier, are figured and described in "Ossemens

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A

GONIOPHOLIS CRASSIDENS. (nat. size.)

Fossiles," tome v. p. 161, Pl. X.; together LIGN. 39.-A TOOTH OF with vertebræ, which were supposed to belong to the same species of saurian."

some

The teeth and bones vary considerably in size : appear to have belonged to individuals not more than eight or

A lithograph of the left-hand specimen is given in the third edition of my "Wonders of Geology," 1839.

2"Des os de Crocodiles des sables ferrugineux du dessous de la Craie, trouvés dans le Comté de Sussex, par M. Mantell." After describing the geology of that part of England from the account given in my "Fossils of the South Downs," then recently published, Baron Cuvier observes: "M. Mantell a bien voulu me communiquer quelquesuns de ses morceaux, et j'y ai reconnu, comme lui, des dents et des vertèbres appartenant manifestement à ce genre (Crocodiles).-Il se trouve parmi les vertèbres une quatrième dorsale, une du milieu de la queue, et une d'un peu plus loin, provenant d'un individu de neuf à dix pieds de long. Les vertèbres sont un peu concaves aux deux extrémités, ce qui les rapproche du crocodile de Caen, et du deuxième de ceux de Honfleur. Les dents sont pour la plupart plus obtuses même que dans nos crocodiles vulgaires, et ressemblent en ce point à la seconde du Jura que j'ai décrite ci-dessus."- Oss. Foss. tome v. p. 163. Paris,

ten feet in length; others are twice as large, and indicate reptiles eighteen or twenty feet long.

It is not unusual to find specimens of these teeth partly decomposed, and disclosing the successional germ; proving, that as in the crocodile, the tooth is composed of a series of cones enclosed within each other, the outer or old crown being burst by the pressure of the upward growth of the included one. Hence, at whatever age the tooth of a crocodile is removed, we find, either in the socket, or in the cavity of the old tooth, a smaller cone ready to supply the place of the latter, when broken or destroyed. This succession is very frequently repeated, and it is from this cause that crocodilian teeth in a fossil state are always so sharp and well defined, for they are as perfect in the adult and aged animals as in the young state.

DERMAL BONES OF GONIOPHOLIS.—(Lign. 40.)—The most remarkable character in the interesting specimen we are now examining is the dermal cuirass, of which the remains, consisting of osseous scutes, are scattered promiscuously over both blocks of stone, some having the inner, and others the external surface exposed. Several of these dermal plates are entire (one is represented in Lign. 40); they are six inches in length, and two and a-half in width. Fragments of these scutes are often found in the Wealden strata; and the earliest specimens I collected, from the resemblance of their corrugated surface to that of the costal plates of the carapace of the soft-skinned turtles (Trionyces), were figured and described as such in my "Fossils of Tilgate Forest," Pl. VI. fig. 8; that opinion being sanctioned by Baron Cuvier, who, with his characteristic liberality and kindness, sent me models of the eocene turtles of Paris, for comparison. The occurrence of similar scutes associated with crocodilian bones in the Swanage specimen, first led me to suspect their true character, which became manifest on clearing out a perfect specimen: their nature I will briefly explain.

In the loricated tribe of reptiles, as the Crocodiles, the external integument encloses numerous bony scutes, or scut

1 There were a considerable number of teeth of crocodilian reptiles from the Wealden in my collection, but I do not know in what part of the Museum they are placed.

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