186 DR. J. E. GRAY ON THE TORTOISES. [ Mar. 11, 
A. Claws 4.4. Head covered with a soft skin, divided into small 
shields on the crown and temple. Nose conical, produced. 
The chin with a series of distinct shields at the under edge of 
the beak. The alveolar surface of the jaws very wide, with 
two well-marked subparallel ridges. Gular shield short, band- 
like. 
16. Terraonyx. Batagur, Gray, Cat. Shield Rept. p. 35. 
B. Claws 5.4. Head covered with a thin skin. Nose subconical, 
more or less produced. Alveolar surface of the jaws with a 
single well-marked angular ridge. Gular shields triangular, 
moderate. 
a. The alveolar surface of the jaws very wide and well-developed, 
with a denticulated ridge parallel to the outer edge. The in- 
ternal edge of the alveolar surface, which edges the internal 
nostrils, is denticulated ; it must not be confounded with the 
second ridge in the genus Tetraonyx. 
17. Kacuuea, Gray, Cat. Shield Rept. p. 35. 
b. The alveolar surface narrower, with a single well-marked ucute 
ridge. Back of the thorax high, subangular ; keels subnodose. 
The sternum high, keeled on each side. 
18. PANGSHURA. 
Tribe VI. Pseupemyp1na. The alveolar surface of the jaws very 
broad, with one or two strong ridges or grooves. Internal 
nostrils subposterior. Toes elongate, slender, covered with a 
few small bands, united by broad webs to the claws. Hind 
feet fringed. The cavity of the thorax simple, not much con- 
tracted at the ends. America. 
* Sternal costal suture simple, normal. 
19. Psrupemys, Gray, Cat. Shield Rept. p. 33. 
20. Tracuemys, Agassiz. 
** Sterno-costal suture with four sterno-lateral shields. 
21. DERMATEMYS, Gray, Cat. Shield Rept. p. 49. 
Tribe I. GrorMyYDINA. 
1. GroremMyDA, 
Grormypa Granpis. The skull (as seen through the skin) in 
a very large old and a younger stuffed specimen, like the skull of 
Cistudo, is destitute of any zygomatic arch uniting the orbit to the 
ear-cavity of the temporal bone, the temple and temporal muscles’ 
behind the orbit being only covered with a skin protected by thin, 
small, tessellated plates. 
