364 



SKELETON OF BIRDS. 



some power of motion; and the lower, instead of directly articu- 

 lating with the cranium by a projecting condyle, as in the 



FIG. 177. SKELETON OF VULTURK. 



vc, cervical vertebras ; vs, sacral vertebra? ; vq, caudal vertebra ; cl, clavicle ; A, hume- 

 rus ; o, bones of forearm ; ca, carpus ; ph, phalanges ; st, sternum ; /, femur ; t, tibia ; 

 ta, tarsus. 



Mammalia, is suspended to a moveable bone named the tympanic 

 bone, or os quadratum, which is analogous to a portion of the 



temporal bone de- 



orwt. partition. tached from the 



main part, to which 

 it is united in the 

 preceding class. 

 Each of the branches 

 of this jaw is com- 

 posed of two pieces, 

 oiqaadramm. i ns tead of being 

 formed of a single 

 bone; and it is by 

 a cavity, not by a projecting condyle, that it articulates 



Lachrymal 

 bone. 



...Cranium. 



Upper Jaw 



Juyal Lower 

 bone. Jaw. 



Fio. 178 SKULL OF EAGLE. 



