TK1ONYX. 



13 



7. Trionyx hurum. 



Trionyx hurum, Gray, Syn. Rept. p. 47, pi. x ; id. III. Ind. Zool. ii, 



pi. Ixvi ; Bouleng. Cat. Chel. Sfc. p. 249. 

 Tnonyx ocellatus, Gray. III. Ind. Zool. i. pi. Ixxviii : Theob. P. A. S. 



B. 1875, p. 174, pi. iv ; id. Cat. p. 29. 

 Trionyx gangeticus, Giinth. Rept. B. I. p. 47. 

 Trionyx buchanani, Theob. P. A. S. B. 1874, p. 78. 

 Trionyx gangeticus, part., Theob. Cat. p. 28. 





Fig. 5. Trionyx hurum (young). 



Costal plates eight pairs, the last well developed and in contact 

 throughout on the median line; two iieurals between the first 

 pair of costals ; plates coarsely pitted and vermiculate. Epiplastra 

 narrowly separated from each other in front of the eutoplastron, 

 which forms an obtuse or a right angle ; plastral callosities very 

 large, hyo-hypoplastral, xiphiplastral, and in old specimens ento- 

 plastral. Dorsal skin of young with longitudinal ridges of small 

 tubercles. Head moderate ; snout (on the skull) a little longer 

 than the diameter of the orbit ; iuterorbital region, in the adult, as 

 broad as the nasal fossa; postorbital arch somewhat more than 

 half the diameter of the orbit in the adult ; inaudible without 

 strongly raised inner edge or longitudinal symphysial ridge ; the 

 diameter of the mandible at the symphysis exceeds the diameter of 

 the orbit. Olive-brown above and beuealh ; head, neck, limbs, and 



