752 



PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



direction of the centre of gravity may fall behind the hind legs, and then 

 the animal falls over backward. In rearing, the fore legs and hind legs 

 are parallel to each other and alwaj's somewhat diagonal ; likewise, both 

 fore legs are not elevated simultaneously, but one somewhat precedes the 



Fig. 310.— Rk.ahtnc. (.Colin.) 

 A B, line of action of ilm-stimal iniiaoles: F G. slnteus maximus; D C, isohio-tibial muscles; DE, 

 pyramidal prolongation of the vastus. 



other. The return to the normal condition is accomplished by the drop- 

 ping of the head and neck, the return of the fore legs from their flexed 

 to the extended condition, so that gravitation alone is sufficient to cause 



