THE STUDY OF THE RABBIT. 77 



STEP 4. Mouth and teeth. 



Mouth and lips. Position of mouth. Upper lip cleft 

 up to nose. Why ? Recall what pupils have observed 

 about advantage of this when gnawing. Lower lip 

 small. 



Jaws. Have pupils note that we can move only our 

 lower jaw, not our upper jaw, and can move it up and 

 down, from side to side, and slightly, from front to back. 



Fig. 19. Skull of Rabbit 



The up-and-down movement enables us to bite. How 

 do the other movements aid us in grinding our food? 

 Movements of rabbit's lower jaw are similar; but the 

 movement from front to back, best seen when he is 

 " chewing his cud," is greater. 



Teeth. Have pupils ascertain and tell about the kinds 

 of teeth in their own mouths : the chisel-shaped biting 

 or incisor teeth in front of each jaw ; the longer, pointed 

 teeth next to these, the dog teeth or canine teeth, one 

 on each side of the incisors ; several flat, rough grinding 



