OR LIGAMENTS. 127 



other, to prevent the tearing of the two toes asunder during 

 their rapid and bounding movements, which are not com- 

 patible with the extensive movements of the toes of carni- 

 vorous species. In the slow-moving extremities of the ele- 

 phant, the rhinoceros, and the hippopotamus, there is no 

 ligamentum teres to fix the head of the femur to the cotyloid 

 cavity, nor do we find it in the kangaroo^ the sloths, or the 

 monotrema, nor in the sedate orangs, which so much ap- 

 proach the human species. 



