THE HORSE ANATOMY AND PHYSIOLOGY. 



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pear. By the end of the first year these six incisors, reach 

 their full size. The first teeth dill'er from the permanent, in be- 

 ing more rounded in front and hollow towards the mouth, show- 

 ing the outer edge at first much higher than the inner. After 

 the foal begins to use them in eating, the outer edge wears 

 down, but the corner nippers keep their original appearance. 



Fig. 2 shows the inside view of the lower jaw at six months. 

 The central nippers are almost level, and have the black "mark" 

 in the middle of each, wide and faint. The outer edge, but not 

 the inner, of the middle teeth now show wear. About the 

 ninth month the inner edge of the middle teeth will appear worn. 



FIG. 3. ONE-YEAR-OLD MOUTH. 



Fig. 3 shows the lower jaw at one year. The outer and 

 inner edges of all the nippers are partly worn, excepting the 

 inner edges of the corner teeth which have not come to that yet. 



FlO. 4. TWO-YEAR-01,1) MOTTTH. 



Fig. 4 shows lower jaw at two years. At a year and a half 

 the "mark" in the central pair becomes very faint from wear; 



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