PELOCHELYS. 15 



10. Trionyx cartilagineus. 



Testudo cartilaginea, Boddaert, Epistola ad W. Roell, 1770. 

 Trionyx ornatus, Gray, P. Z. S. 1861, p. 41. pi. v ; G'unth. Rept. B. L 



p.48,pl.vi,fig.B. 

 Trionyx stellatus, var. javanicus (Geoffr.}, Theob. P. A. S. B. 1874, 



p. 79. pi. iii ; id. Cat. p. 30. 



Trionyx ephippium, Theob. P. A. S. B. 1875, p. 177, pi. v. 

 Trionyx cartilagineus, Bouleng. Cat. Chel. fyc. p. 253. 



Costal plates eight pairs, the last well developed and forming a 

 median suture behind the last neural ; a single neural between the 

 first pair of costals ; dorsal plates coarsely pitted and vermiculate. 

 Dorsal skin of young with longitudinal ridges of small tubercles. 

 Epiplastra in contact, or narrowly separated, in front of the 

 entoplastron, which forms an obtuse or a right angle ; plastral 

 callosities well developed in the adult, hyo-hypoplastral and 

 xiphiplastral, and coarsely sculptured like the carapace. Head 

 moderate; snout (on the skull) considerably longer than the 

 diameter of the orbit ; iuterorbitai region, in the adult, as broad as 

 the nasal fossa, or a little narrower ; postorbital arch very narrow, 

 one third or one fourth the diameter of the orbit ; mandible with 

 a strong ridge along the symphysis, the diameter of which equals 

 or exceeds the diameter of the orbit. Olive-brown above and on 

 the chin ; head and chin with numerous yellow spots, the largest 

 of which are below the temple ; dorsal disk of young light-dotted, 

 and usually with a few large blackish spots ; lower parts white. 



Size of T. hurum. 



Hob. Pegu, Tenasserim, Siam, Camboja, Malay Peninsula, 

 Sumatra, Borneo, Java. 



Genus PELOCHELYS, 

 Gray, P. Z. S. 1864, p. 89. 



Outer extremities of the nuchal plate overlying the second 

 dorsal rib; neural plates well developed. Limbs completely 

 exposed. Hyoplastron distinct from hypoplastron ; not more 

 than five plastral callosities. Bony choanse between the orbits ; 

 jaws weak ; postorbital arch as broad as the diameter of the orbit ; 

 posterior border of pterygoids free, without ascending process. 



A single species. 



11. Pelochelys cantoris. 



Chitra indica, part., Gray, Cat. Tort. p. 49 ; Gunth. Rept. B. I. p. 50, 



pi. vi. fig. C. 



Gymnopus indicus, Cantor, J. A. S. B. xvi, 1847, p. 616. 

 Pelochelys cantorii, Gray, P. Z. S. 1864, p. 90, figs. ; Theob. Cat. 



p. 28 ; Bouleng. Cat. Chel. $c. p. 263. 



Costal plates eight pairs, the last well developed and forming a 

 median suture ; a single neural between the first pair of costals ; 

 plates coarsely pitted and vermiculate. Dorsal skin of young 



