MEGATHERIUM. 155 
The toes of the fore-foot are terminated by 
large and powerful claws of great length ; the 
bones, supporting these claws, are composed 
partly of an axis, or pointed core, (o,) which 
filled the internal cavity of the horny claw ; and 
partly of a bony sheath, that formed a strong 
case to receive and support its base. These 
claws were set obliquely to the ground, like the 
digging claws of the Mole, a position which 
made them instruments of greater power for the 
purpose of excavation. 
Posterior Extremities. 
The jjehis of the Megatherium (PL 5, Fig. 
2. p.) is of vast solidity and expanse ; and the 
enormous bones of the ileum (r) are set nearly at 
right angles to the spine of the back, and at 
their outer margin, or crest, are more than five 
feet asunder, very much exceeding the diameter 
across the haunches of the largest Elephant : the 
crest of the ileum, (s,) is much flattened, as if by 
the pressure of the armour. This enormous size 
of the pelvis would be disproportionate and in- 
convenient to an animal of ordinary stature and 
instrument of peculiar power for the purpose of digging ; and 
each presenting an extraordinary enlargement and elongation of 
the extreme bones of the toes, for the support of long and mas- 
sive claws. At PI. 5, Figs. 18, 19, the anterior parts of these 
animals are represented, and show how large a proportion the 
claws bear to the other parts of the body. 
