TESTUDINIDA, — CXXIII. 211 
ing obscure with age. NN. Y. to Mo. and S., in dry woods. Repre- 
sented S. by T. triunguis (Agassiz). Hind feet mostly 3-toed ; 
color pale yellowish, with few spots. Southern, N. to Penn. 
624. T.ornata Agassiz. “Shell round, broad, flat, without keel, 
even when young.” Iowa and W. 
Famity CXXUI. TESTUDINIDAS. (Tue Lanp 
TORTOISES.) 
Carapace strong, thick, ovate, generally very convex and falling 
off abruptly at both ends; caudal shields united into one; plastron 
very broad, covering the whole under surface, the anterior part 
sometimes movable on a transverse hinge. Legs and feet club- 
shaped; toes firmly bound together by the integument, only the 
blunt claws being exserted. 
Herbivorous Turtles, entirely terrestrial, inhabiting the warmer 
parts of both continents; about 20 species are known, 
317. GOPHERUS Rafinesque. 
625. G. polyphemus (Daudin). “GorHer Turtiz.” Brown- 
ish, head almost black ; yellow below; fore limbs large and strong ; 
hinder short, rounded ; plastron projecting forward beyond cara- 
pace. L.15. 8. States, N. to N.C., in pine barrens; herbivo- 
rous and gregarious; burrows in the ground like a wood-chuck. 
(wodvpypos, croaking.) 
Passing over the order Crocop1L1A, the highest in development 
among the recent reptiles, an order having no representatives 
within our limits, we take up next a group originally an offshoot 
from the Reptilian series, but now, if only living forms were taken 
into consideration, one of the most sharply defined of the classes of 
Vertebrata, the Birds. 
(For additional species of Reptilia, see Appendix.) 
