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Show 1873.] DR. J. E. GRAY ON THE TRIONYCHlDcE. 57 cies of the genus or an undergrown state of the animal, the upper surface of the odd bone is rather callous for a great part of its length, and with a few pits on its hinder margin ; therefore I strongly suspect that, in the adult specimens, the bone is united to the ribs with a callous and pitted surface, as in the Trionychina. Fig. 8. Dogania sulrplana. 1. D O G A N I A S U B P L A N A . (Fig. 8.) Head pale-spotted, with a dark streak from the side of the nose to the orbit. Trionyx subplanus, Geoff. Ann. Mus. iv. p. 11, t. 3. fig. 2; Gray, Illustr. Ind. Zool. t., from Hardwicke's drawing (young). Dogania subplana, Gray, Cat. Tort. B. M . p. 49, 1844 ; Ann. & Mag. N. H.xii. 1863, p. 158 ; Cat. Sh. Rept. p. 69, t. 33, inspirit; P. Z. S. 1862, p. 265, 1864, p. 83, figs. 1, 2, 3 (skull), 1869, p. 213; Suppl. Cat. Sh. Rept. p. 106, fig. 35 (skull). Trionyx frenatus, Gray, Cat. Sh. Rept. p. 67 (part). Potamochelys ? frenatus, Gray, P. Z. S. 1864, p. 87. Sarbieria frenata, Gray, P. Z. S. 1869, pp. 212-220; Suppl. Cat. Sh. Rept. p. 100. Hab. China and Formosa (Swinhoe); Singapore ?(Wallace) ; not the Ganges, as erroneously stated by Dumeril and Bibron. Gen. Hardwicke's specimen, figured in his drawing, which is copied in the ' Illustrations of Indian Zoology,' is in tbe Museum. The front lateral bone of the sternum has indications of rugosity on the inner part of the hinder edge ; but this rugosity is of an irregular shape, not like the linear lateral callosities of Aspilus. All the other sternal bones are smooth ; but the animal is evidently immature, just noticed as a variety of Trionyx frenatus. The sternum of the specimen described in Cat. Sh. Rept. as Sarbieria frenata, brought from Singapore by Mr. Wallace, is about half the size of the former. The front and hinder lateral bones are marked with a number of dots and inosculating lines, as if they were to have, when they become older, callosities covering the greater part of the central lateral portion, very unlike the linear callosities of Aspilus. |