BONES OF THE LEG AND WING OF BIRDS. 



177 



being closely welded together as in Fig. 153, are found to 

 be separate, and the carpal bones, of which only two were 

 apparent in the full-grown wing, are now separate and four 

 in number. The wing at this stage looks more like a three- 

 toed foot. Fig. 155 shows the appearance of the wing of an 

 embryo bird. 



As the bird develops, the bones of the fingers gradually 

 approach and some of the bones grow together till they 

 present the appearance shown in Fig. 153. 



158. The bones of the leg grow together in the same way. 



fibula 

 tibia 



tarsii-sJ 



metatarsus 



phalanges < 



I 



156. BONKS OF THE EIGHT LEG OF AN ADULT BIRD. Only tho lower portion of 



the tibia arid fibula is drawn. 



