34 CINOSTERNID &. 
Ozotheca, Agassiz, l. ce. p. 424; Leconte, Proc. Ac. Philad, 1859, 
sO: 
Cinosternum, Agassiz, l. e. p. 426; Leconte, 1. c. 
Thyrosternum, Agassiz, l. c. p. 427; Leconte, 1. e. 
Platythyra, Agassiz, 1. c. p. 429. 
Fig. 11. 
Skull of Cinosternum leucostomum. 
Carapace more or less depressed; marginal shields, one azygos 
nuchal and 11 pairs. Plastron articulating with the marginals by 
suture, front and hind lobe movable; gular shield single or absent : 
pectoral shields not extending on the bridge. Postorbital and 
temporal arches moderate. Digits webbed; fingers all clawed, 
outer toe clawless. Tail short. 
America, north of the Equator, 
