MEGATHERIUM. 125 



From the enormous width of the pelvis, it follows also 

 that the abdominal cavity was extremely large, and the 

 viscei'a voluminous, and adapted to the digestion of vege- 

 table food. 



The form and proportions of the thigh-bone, (v) are not 

 less extraordinary than those of the pelvis, being nearly 

 three times the thickness of the femur of the largest Ele- 

 phant. Its breadth is nearly half its entire length, and its 

 head is united to the body of the bone by a neck of unusual 

 shortness and strength, twenty-two inches in circumference. 

 Its length is two feet four inches, and its circumference at 

 the smallest part, two feet two inches ; and at the largest 

 part, three feet two inches. Its body is also flattened ; and by 

 means of this flatness, expanded outwards to a degree of 

 which Nature presents no other example. These pecuHari- 

 ties in the femur appear to be subservient to a double pur- 

 pose : first, to give extraordinary strength by the shortness 

 and solidity of all its proportions ; and secondly, to afford 

 compensation by its flatness outwards; for the debility 

 which would otherwise have followed from the inwai'd po- 

 sition of the sockets, (t.) by which the femur, (u,) articulates 

 with the pelris. 



The two bones of the leg (x, y,) are also extremely shorty 

 and on a scale of solidity and strength, commensurate with 

 that of the femur that rests upon them. This strength is 

 much increased by their being united at both extremities ; a 

 union which is said by Cuvier to occur in no other animals 

 except the Armadillo and Chlamyphorus ; both of which are 

 continually occupied in digging for their food. 



The articulation of the leg with the hind-foot is admira- 

 bly contrived for supporting the enormous pressure of down- 

 ward weight ; the astragalus (z,) or great bone of the in- 

 step, being nine inches broad and nine inches high, is in due 

 proportion to the lower extremity of the tibia, or leg-bone, with 

 which it articulates ; and rests upon a heel-bone, of the extra- 

 ordinary length of seventeen inches, with a circumference of 



11* 



