| OCR Text |
Show 188 DR. j. E. G R A Y O N T H E TORTOISES. [Mar. 11, eentral hook j the lower jaw moderately strong, covered in front with a convex homy sheath. Toes strong, included in the skin to the claws, covered above with band-like shields. A skull received from Mr. Oldham, which appears to belong to this species, may be thus described:-Skull depressed, nose nearly erect from upper lip ; crown rather convex, tapering behind ; orbit large, circular, lateral, subsuperior; zygomatic arch imperfect, rather broad in front, about half as broad as the back edge of the orbit, and tapering off behind just before it reaches the upper edge of the small circular tympanic cavity; palate flat, broad, with a short shallow concavity behind each internal nostril; the lateral edge of the upper jaw nearly straight, with a sliglitly produced broad central beak, and with a narrow alveolar plate having a slight groove parallel to the short outer edge for the greater part of its length; lower jaw weak, erect on the side, shelving in front, with a central conical prominence in front, and with a straight, thin, sharp edge, without any dilatation of any kind. Tribe II. GEOCLEMMYDINA. 3. GEOCLEMMYS. 1. GEOCLEMMYS GUTTATA. A beautiful skeleton is in the British Museum, and a skeleton without lower jaw in the Museum of the College of Surgeons, no. 977a. Skull thin, crown slightly arched, nose erect; orbit lateral, very large ; zygomatic arch broad, short; palate flat behind ; lower jaw slender; side edges of the upper jaw slightly arched, and with a notch iu front; alveolar groove very narrow, even; mastoid bone conical, produced, hollow. Toes short, strong. 2. GEOCLEMMYS SEBAE. Specimen in spirit in the British Museum. Nose rather produced, shelving to the lip below, triangular, soft, in a notch on the upper edge of the upper beak ; alveolar process linear, marginal ; upper beak with a straight edge and a very slight acute central notch, lower hooked and acute in front. Toes short, included in the skin to the base, but slightly separate, conical, with a central series of narrow six-sided scales above; web very slight, if any. 3. GEOCLEMMYS MUHLENBERGII. An adult specimen in spirit, from North America, with the yellow spots on the occiput well-marked. The beaks have an even lateral edge and an acute notch in the centre in front; the lower beak convex and rounded below; crown rather convex, dark olive, with black spots. Toes united in the skin to the claws, with a few band-shaped shields above. The upper alveolar surfaces rather broadly linear, with a submarginal internal ridge ; the lower with a continuous submarginal groove, rather broad, and produced, with a sharp edge, in front. |
