304 MAMMALS 



]*]vi(lentl_y the rabbit's sense of smell is well developed for 

 we (}ften see it moving the end of the nose and upper lip 

 as though in tlie act of snitting. 



Mouth and teeth. — The mouth is Iwunderl by soft lips 

 ami each jaw is furnislied with teeth of two sorts, the in- 

 cisors and molars. Theie are two pairs of li;ing, curvetl in- 

 cisors in the front of the mouth, one i^air on the lower jaw 

 and one jxiir on the upper. These liave sharp, chisel-like 

 edges which meet together and form a ver_y efficient gnaw- 

 ing apparatus. Just behind the large pair of incisors on 

 the upper jaw is a second pair of small, scarcely noticeable 

 incisors. The front surfaces of the incisors are covered 

 with a very hard enamel, while the remaining portion of 

 these teeth are of a softer material. Thus it happens that 

 in gnawing the softer back portions are \A'orn a^vay leaving 

 a sharp cutting edge of enamel in front. Moreover, these 

 teeth grow as fast from their roots as they are worn off by 

 gnawing. This is also true of the teeth of rats, mice, 

 and other gnawers. The upper lip of the ral^bit is split 

 in the middle so as to expose the incisors anil facihtate the 

 work of gnawing. 



Back of the incisors there is a sj^ace on the jaws along 

 which no teeth are found. In a dog's mouth, tlie canine 

 teeth occupy some of this space. Finally, far back in the 

 rabbit's mouth are the molars, or grinding teetli, six pairs 

 above and five pairs below. The upper and lower molars 

 meet by flat, corrugated sui-faces. The lower jaw has a 

 sliding, forward and backward movement, \\liile chewing, 

 thus grinding the food between the sli(hng siu'faces of 

 the two opposing molars. 



The food. — The rabbit is a vegetarian ])ure and simple. 

 It lives upon clovers, grasses, buds and bark of trees, etc. 



