PREHENSION OF FOOD IN GENERAL. 195 



also so modelled in these animals as to be of essential service 

 in introducing the food into the mouth. The upper lip of the 

 horse, long and flexible, and endowed with great sensibility, 

 gathers together the tuft of grass, then the nippers seize and 

 detach it, when the tongue carries it backwards to fall under 

 the molar teeth. If the lips of a horse are turned inside out, 

 and retained in that position by means of ligatures, he tears 

 wisps of hay from the rack, but drops them on the ground, 

 unable to introduce them into his mouth. 



The ox has not the same advantage from the upper lip. It 



is short, thick, not flexible, and too little distinct from the 



muzzle. The defect of incisor teeth in the upper jaw still 



more distinguishes the mode of prehension in the ox from that 



in the horse. Here the tongue takes on itself a larger share 



in the office. It is long, susceptible of much protraction, and 



capable of being twisted on itself while it is covered on its 



upper surface with papillse having horny sheaths. AVhen the 



ox is on pasture the tongue issues from the mouth, is thrown 



to one side, and, turning upon itself, seizes a tuft of grass 



and draws it to the entrance of the mouth, where it is held 



fast between the lower incisors and the rim of the upper 



jaw, and, being torn away by a slight movement of the head, it 



is quickly carried between the molar teeth. When the grass 



or hay lies loose on the ground, it is gathered with the tongue 



and carried into the mouth. If the fodder is in the rack, the 



tongue is thrust between the bars to seize it ; when the food 



is in grains, as oats, or in the form of meal, it is still with the 



tongue that it is taken up. 



The sheep makes rather less use of its tongue than the ox : 

 the goat makes an approach to the horse in the use of the 

 upper lip : the same is the case with the mouflon, the gazelle, 

 and the antelopes, when they eat dry comminuted substances ; 

 but when they are on pasture they cut it close to the root be- 



