io82 



Rural School Leaflet. 



Fig. 35. — Lower nippers 

 an etght-year-old horse 



of 



marked changes in shape, becoming roundish on the inside, and the 

 intermediates are also somewhat modified. If the horse'^ lips are parted 

 and the mouth is viewed from the fiont, it will be noted that the central 



ones will appear much darker colored and 

 longer than they did at three or four. This 

 is due to the shrinking or receding of the 

 gums. 



Seven years old. — At seven years of age, 

 the cups have disappeared from the inter- 

 mediate teeth, although small dark spots 

 may often be seen. The comer teeth still 

 retain their cups, though they are quite 

 shallow. 



The side view of a seven-year-old mouth 

 shows one marked characteristic. The lower 

 corner teeth seldom extend as far backwards as the upper ones do. 

 Only in rare cases do all four comer teeth meet accurately. The result 

 is that the face of the tooth in the rear recedes, while that part of the 

 tooth not in wear projects downward, forming more or less of a notch. 

 Eight years old. — At eight years of age, the cups have disappeared 

 from the teeth in the lower jaw. One must not be misled by the slight 

 dark colored indentations that are still present, for they are not deep 

 enough to be called cups (Fig. 35). It is well to bear in mind that, 

 from the time when the teeth in the lower jaw are well up and in wear, 

 to the time the cups have disappeared in the lower jaw, is three years. 

 The shape of the tooth has undergone marked changes. Compare 

 Fig. 28 with Fig. 35 and Fig. 30 with Fig. 36. In the first instance 

 the teeth were thin from outside to inside, and comparatively broad 

 from right to left, while in the latter case 

 they are much thicker from inside to outside. 

 They have become more triangular in shape. 

 If viewed from the side, they will appear some- 

 what longer and will meet at a sharper angle 

 than they did when the horse was younger. 

 As years go by, the angle of the teeth in- 

 creases. At three years of age, the upper 

 and lower teeth meet nearly vertically, while 

 at twenty they meet at an angle of nearly 

 forty-five degrees. 



Nine years old. — The teeth in the upper jaw retain their cups a much 

 longer time; in fact, just twice as long, disappearing in six years from 



Fig. 36. — Side view of the 

 nippers of an old horse 



