The Framework of the Bird 



99 



In the chicken, we next come to a single long bone 

 called the tarsus, which is, in life, covered with scales. 



J^'iG. 73. — Skeleton of an Ostricti 

 leg and foot. 



Fig. 74. — Human leg and foot. 



In the embryo it is composed of several separate bones.* 

 The simplest interpretation we can give to the foot of 



* These correspond in ourselves to the bones of the upper foot and the 

 second row of carpals, this joint of the leg coming, therefore, really between 

 the bones of the ankle, instead of, as in ourselves, between the ankle and the 

 lower part of the leg. 



