AND THEIR FUNCTIONS. 



123 



a length that a bird seems to have two thighs, one next the 

 shank and the other, the " ischion," extending from the 

 rump to the aforesaid thigh.* Further, he says that birds 

 have sinewy and not fleshy legs.t Some consider the 

 " ischia " of birds to be the pelvic bones, but this explana- 

 tion makes Arisotle's statements very difficult to understand. 

 The astragali, or knuckle-bones, which chiefly transmit 

 the downward thrust of the tibial bones, are often referred 

 to by Aristotle. Those only which were elegant or fairly 



FIG. 6. 



LEFT ASTRAGALUS OF A SHEEP. 



symmetrical were used by the Ancients in playing various 

 games and for divination, and it is only to such astragali as 

 these that Aristotle usually gave the name. It was on 

 account of want of symmetry that he excluded Man and 

 most animals with many toes from among animals having 

 astragali, although he refers to the twisted knuckle-bone of 

 the lion, and calls the unsymmetrical and comparatively long 

 and thin knuckle-bone of the lynx a half astragalus, t He 

 says that most of the animals with astragali are cloven- 



* De Anim. Incessu. c. 11, 7106. 



\ H.A. ii. c. 2, s. 7 ; P. A. iv. c. 12, 695a. 



I H. A, ii. c. 2, 8. 10. 



