IN THE LOWEE ANIMALS, ETC. 249 



character resemble those of the ruminants, differ 

 from them in their great length before dividing 

 into roots. (Fig. 44.) This division does not 

 commence until the crown is considerably worn 

 down, consequently the horse never possesses a 

 perfect crown, with perfect roots, which latter are 

 only found in old horses. 



Fig. 45. — Grinding Surface of Molar of adult Horse, slowing arrange- 

 ment of folds. 



The coronoid process of the lower jaw offers, as 

 in ruminants, a very limited surface for the inser- 

 tion of the temporal muscle ; and its attachment 

 to the temporal muscle is equally circumscribed ; 

 but this is amply compensated by the large surface 

 provided for the insertion of the pterygoid muscles 

 in the broad angle of the lower jaw, supplying 

 powerful lateral motion. 



The condyle is more rounded at its margins than 

 in ruminants, and the glenoid cavity is more con- 

 tracted, hence the masticating action is from side 

 to side, instead of the circular motion observed 

 in the sheep. 



The horse is much more delicate in the selec- 



