37 



EMYS RUBRIVENTRIS.— Lecon/e. 



Plate VI. 



Characters. The shell is oval, elongated posteriorly; entire in front, emargi- 

 nate behind; ecarinate and longitudinally rugous; sternum red; jaws denticulated. 



Synontmes. Testudo rubriventris, Leconte, Ann. Lye. Nat. Hist. N. Y., vol. iii. p. 101. 

 Emys serrata, Say, Jour. Acad. Nat. Scien. Philad., vol. iv. p. 204. 

 Emys serrata, Harl., Med. and Phys. Res., p. 154. 

 Emys serrata, Gray, Syn. Rept. p. 29, spec. xxiv. 

 Emys irrigata. Bell, Manuscript Notes. 



Emys rubriventris, Durn. et Bibr., Hist. Nat. des Rept., torn. ii. p. 281. 

 Emys irrigata. Bum. et Bibr., Hist. Nat. des Rept, torn. ii. p. 276. 

 Potter or Red-bellied Terrapin, Vulgo. 



Description. The shell is oval, much elongated, and broadest at its posterior 

 part; convex ecarinate; full and entire in front, but emarginate behind. There 

 are five vertebral plates; the anterior is urceolate, hexagonal, and smallest in front; 

 the second, third and fourth are also hexagonal, the latter irregularly so, with its 

 posterior margin re-entering; the fifth is heptagonal, its anterior margin convex 

 and projecting into the fourth plate. The first lateral plate is triangular, its basis 

 rounded and directed downwards; the second and third are pentagonal; the fourth 

 is sub-rhomboidal, with its inferior margin angled; all these plates are longitu- 

 dinally rugous. There are twenty-five marginal plates; the nuchal is quadrilateral, 

 elongated, narrowest at its anterior margin, where it is sometimes finely serrated. 

 The first marginal plate is irregularly quadrilateral, broadest in front, narrow and 

 rounded behind; the second is also quadrilateral, with its internal and superior 



