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 



_ t 



ta 



FIG. 177 SKELETON OF VULTURE. 



vc, cervical vertebras ; vs, sacral vertebrae ; vq, caudal vertebras ; cl, clavicle ; Ji, hume- 

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

 ta, 



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- 

 tached from the 

 main part, to which 

 it is united in the 

 preceding class. 

 Each of thebranches 

 of this jaw is com- 

 posed of two pieces, 



J b u one! L jaw e . r 8 quadratnm< instead of being 

 FIG. 178.-SKULL OF EAGLE. formed of a single 



bone; and it is b] 

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



Upper j a 



