TORTOISES. 29 



centric rings, which are often impressed ; animal grey, black- 

 spotted and lined. 



a. Smooth, highly coloured. N. America. Presented by Gen. 

 Th. Hardwicke. 



b. Like a. Presented by the Earl of Derby. 



c. Like a. Presented by Gen. Th. Hardwicke. 



d. Smooth, distinctly ringed, 6 inches. N. America. Presented 



by Gen. Th. Hardwicke. 



e. <Srf. Shell only: like d. 



g. Shell and animal, dry : like d. 



h. Shell only (young) ; the three central vertebral plates with a 

 central tubercle, the hinder tubercle orbicular. M. tuberculi- 

 fera, Gray, B. M. California. Mr. J. Drummond's collection. 



i. Shell only. Mus. Sloane. 



4. Tetraonyx, Lesson. 



Head moderate, covered with a thin skin ; chin not bearded. 

 Feet largely webbed. Toes 4-4. Tail moderate. Shell oval, 

 rounded, depressed. Sternum solid, broadly truncated before, 

 nicked behind, affixed to the thorax by a bony symphysis, covered 

 with the end of the pectoral and abdominal plates. Axillary and 

 inguinal plates ? 



The Batagur. Tetraonyx Batagur. Emys batagur, Gray, 

 Syn. 24. Illustr. Ind. Zool. iii. t. Testudo Batagur, B. 



Hamilton, MS. E. Tetraonyx, Schlegel, F. Japon. 43. Tetrao- 

 nyx longicollis, Lesson, Belangefs Voy. 297. Illust. Zool. t. 7. Tet. 

 Lessonii, Dum. et Bib. E. G. ii. 338, t. 16, f. 1. Trionyx Cuvieri, 

 Gray, Syn. Rept. 5. Emys Baska, Gray, Illust. Ind. Zool. t. 

 B. Hamilton MS. Icon, (very young). Dum.et Bib. E. G. ii. 341 . 

 E. Spengleri var. Schlegel, F. Japon. 51. 



Shell suborbicular, depressed, slightly keeled, entire, dilated 

 behind, pale olive. 



Inhabits India, " Calcutta, common," Blythe. Mus. Bell, 

 young. Mus. Paris, of a large size, and young. 



5. Cistuda, Fleming. Kinosternon, part, Bell. Pyxidemys. Fitz. 



Head moderate, covered with a thin hard continued skin. Tots 

 5-4, webbed to the claws, web thick, with a small intermediate lobe 

 between the claws. Tail short. Shell ovate, convex or hemi- 

 spherical. Sternum broad, rounded before and behind, complete- 

 ly closing the cavity of the thorax, affixed to it by a ligamentous 

 symphysis and divided by a cross suture between the pectoral and 

 abdominal plates. Sternal shields 12. Inguinal and axillary 

 plates very small and distinct. Marginal plates 23 — 27. Nuchal 

 plate small or wanting. Old and New World. 



