OCR Text |
Show 54 DR. J. E. GRAY ON THE TRIONYCHlDcE. [Jan. 7, identical with that species. The skin shows the white spots on the underside of the head. 1. LANDEMANIA PEROCELLATA. (Fig. 6, p. 53.) Head olive above, with a black streak from the back edge of the eye, extending along the upper part of the sides of the neck. Trionyx perocellatus, Gray, Cat. Tort. B. M. p. 48 ; Cat. Sh. Rept. p. 65, t. 31 (animal in spirit). Potamochelysl perocellata, Gray, P. Z. S. 1864, p. 86. Landemania 1 perocellata, Gray, P. Z. S. 1869, p. 216; Suppl. Cat. Sh. Rept. p. 96 ; Ann. & Mag. Nat. Hist. 1872, x. p. 338. Landemania irrorata, Gray, P. Z. S. 1869, p. 218, fig. 18; Suppl. Cat. Sh. Rept. p. 96, fig. 31 (sternum, from dried specimen). Trionyx tuberculatus, Cantor's drawings, Gray, P. Z. S. 1861. Potamochelys tuberculatus, Gray, P.Z.S. 1864, p. 87; Suppl. Cat. Sh. Rept. p. 105. Hab. China (Chusan). The specimen figured in the Cat. Sh. Rept. has the head olive, with a few irregular black spots, with a long narrow streak from the back edge of the eye, and two or three streaks from the lower edge of the eye towards the lips ; front extending towards the nostrils ; lips and throat with large white spots ; dorsal disk smooth (in spirit), the odd bone united to the rest of the disk; four sternal callosities distinctly marked, but the front odd bone is smooth. The dorsal disk convex, with a longitudinal depression on each side of the central linear prominence; the odd bone large, transverse, united to the whole length of the dorsal disk. There is a specimen in the British Museum with the sternal callosities not so much developed ; and the odd bone in front of the sternum, which is V-shaped, has short arms, not so long as the breadth of the triangle. It is smooth, and not marked with callosities ; but otherwise the two specimens are exceedingly alike. The skull of the specimen described as Landemania irrorata is tapering in front; between the transverse nose-hole and the orbit about half the length of the diameter of the orbit; palate with a broad shallow impression between the front and the nostrils, which becomes narrower behind ; alveolar surface broad, especially behind. Lower jaw produced in front, triangular, sides rather concave ; alveolar surface concave, broad in front, with a slightly elevated central longitudinal ridge, rather narrower on the sides behind, and deeply concave, with a strong ridge on the outer side. Length from nose to condyle 2\ inches. A skeleton of a specimen received from Mr. Swinhoe. The front bone of the dorsal shield very wide, nearly as wide as the second bone, united through its whole length to the second bone ; front pair of bones to the sternum subcylindrical; the pair of lateral bones on the sternum united together by a minutely dentate suture. Dr. Cantor's drawing, which I had described as Trionyx tuberculatus and Potamochelys tuberculata in the Cat. Sh. Rept. p. 105, is most probably only a variety of this species. |