CHAPTER VI. 



Cbe Digestive System. 



"We find that the sheep can, owing to the conformation of 

 its month and appendages, the lips, thrive on scanty pasture, 

 where an ox or other animal woiild have to struggle for exist- 

 ence. The lips being covered by hair, are protected fi'om in- 

 jury against the ground, in which they come in close contact 

 when the animal is feeding. "We find on examination that the 

 upper lip is cleft, and that the two when together tend to form a 

 point, enabling the animal to virtually crop the grass on a level 

 with the surface of the ground. 



XZhe Ccctb. 



These are the agents by which mastication of the food is 

 carried on. They are hard organs, bony in appearance, firmly 

 implanted in the jaws, and projecting into the interior of the 

 mouth. 



The incisor teeth, or nippers, are in the sheep as well as in 

 other ruminating animals situated upon the lower jaw, the 

 upper jaw with which they come in contact during mastica- 

 tion being covered by a dense fibrous pad. "We find that the in- 

 cisors, unlike the back or molar teeth, are not firmly embedded 

 in the lower jaw, but possess a certain degree of mobility (some- 

 times being mistaken for a diseased condition); this, however, is 

 necessary in order to prevent their injuring the fibrous pad of 

 the upper jaw, against which they press. 



The Incisor Teeth are eight in number when the mouth 

 is perfect, or full, as it is termed. "\Ve find that the lamb when 



