BATAGUR BASRA. 37 



BATAGUR, Gray. 



Thorax and sternum solid, entirely, or nearly entirely, bony in full-grown 

 specimens, united into an immoveable carapace ; shell depressed. Sternum 

 flat in both sexes ; pectoral plates subquadranj^ular, forming- a suture to- 

 gether. Feet with the toes broadly webbed ; claws feeble. 



This genus is confined to the East Indies ; its species grow to a considerably larger size 

 than the Emydes proper, but have the same habits. 



Synapsis of the Species. 



* Four claws anteriorly B. baska, p. 37. 



** Five claws anteriorly. 



Posterior margin of the shell not serrated ; the hind margins of the postgiilars 



meet at an obtuse angle ; shell of uniform colour B. lineatus, p. 39. 



Posterior margin of the shell strongly serrated ; vertebral ridge interrupted by 



prominences. The hind margins of the postgulars meet at an obtuse angle . B. elUotti, p. 40. 



Nuchal plate none ; first vertebral broader than long B. affinis, p. 40. 



First vertebral longer than broad. The hind margins of the postgulars form a 



straight line ; upper shell with three black streaks B. dhongoka,-^.A2. 



Batague baska. The Batagur. (Plate III. figs. B, B'.) 



Emys batagirr, Gray, Syn. Rept. p. 23, and Illustr. Ind. Zool. tab. 



baska, Gray, Illustr. Ind. Zool. tab. 



Trionyx cuvieri. Gray, Syn. Rept. p. 50 (very young?). 



Tetraonyx longicoUis, Less, in Belang. Voy. Ind. Orient., Rept. p. 297. 



baska, Dum. ^ Bibr. Erpet. gen. ii. p. 341. 



lessonii, Dum. ^ Bibr. Erpet. gen. \\. p. 338. pi. 16. fig. 1. Blyth, Journ. As. Sac. Beng. xxii. 



1854, p. 645. 

 Batagur baska. Gray, Shield Rept. p. 35. tab. 16, and tab. 36. fig. 1 (skull). 

 Tetraonyx afiinis (part.). Cantor, Catal. Mai. Rept. p. 6. 



Form. — The most elevated and most convex portion of the shell is in its anterior half 

 whilst the posterior is much depressed and flattened; the greatest -width of the shell is 

 behind its middle. The lower parts of the carapace are flat, the sternal portion being 

 narrow. The width of the sternum between the inguinal incisions is rather more than that 

 between the axillary, and two-fifths of its length. Upper shell subtruncated anteriorly. 



