——  ————  — a ne 
207 
above the zygomatic process appears to be broken off, but the obli- 
quity of its base renders it improbable that it would be the true 
frontal process so largely developed. 
The circular pit for the attachment of the stylohyal bone is pre- 
cisely similar in the Sloths to that in the large fossil genera, and it 
is somewhat remarkable that Prof. Owen, while describing the cha- 
racter in these extinct forms, should have made no allusion to its 
existence in the recent Sloths, even though Cuvier expressly points it 
out. The tongue is largely developed in this family, and the living 
sloth may be seen to make great use of it in taking food into its 
mouth, as was observed by Mr. Ball, in a short communication pub- 
lished in the < Proceedings’ some years back. On the other hand, it 
is long and slender in the insect-feeding tribes, so that the maximum 
degree to which it was developed in the Glossotherium is certainly 
no indication that such was the food of that remarkable genus. 
CuoLervs, Illiger. 
Intermaxillary bones small, produced anteriorly ; postorbital pro- 
cess well-developed; malar bone with a well-marked frontal process, 
but no zygomatic process, the supratemporal process projecting 
backwards or bent a little upwards; pterygoid bones inflated ; 
crotaphite impression approaching near to the occipital ridge; tym- 
panic bone reduced to a simple ring; lower jaw produced ante- 
riorly, straight below, its condyle depressed; teeth =, simple, 
rounded, the anterior ones in each jaw enlarged, trigonal. 
C. didactylus. 
siderable distance from the occiput ; tympanic bone well-developed, 
forming a bulla; lower jaw with a flattened Square process in front, 
deep posteriorly, the lower outline convex, the condyle elevated ; 
teeth =, simple, rounded, the anterior ones similar, small in the 
upper jaw. 
B. crinitus. 
In addition to the character of the pterygoids, which, in the absence 
of actual knowledge, might possibly have belonged to age or sex, I 
find'this species to be clearly distinguishable from those of the next 
genus by the great distance that intervenes between the posterior 
termination of the temporal fossee and the occiput, which is much 
smaller, of a rounder form; the digastric fossee converging a little 
superiorly, instead of diverging as in the other genus. The lower 
jaw also presents a character more decided than the anterior pro- 
