360 THE ANATOMY OF THE HORSE 



Between four and a half and five years, the corner nippers are 

 shed, and the tush protrudes through the gum. These changes are shown 

 in Fig. 7. 



At five tears the mouth is complete in the number of its teeth ; and 

 from this date it becomes necessary to study their aspect in both jaws. 

 Fig. 8 shows the upper teeth at tliis age, by comparing which with Fig. 7 

 the shght growth in the half-year may be traced. In the lower teeth of the 

 same mouth, the edges of the central cavities are much more worn away. 



Fio. 7.— Mouth or the Colt at Fotje and a Half Yeaes. 



\. Anterior maxillary bone. growth, with the edges of the cavity 



1.1. Central nippers, considerably worn down. sharp, and tlie mark verj' plain. 



2. 2. The next pair, fully developed, with their 4. 4. The tushes showing themselves through 



edges slightly worn. the gum, but not full-grown. 



3. 3. Comer permanent nippers, in a state oi 



the central nipper having only a small black speck in the middle of a smooth 

 surface, while the next is much worn, and the corner teeth, though showing 

 the mark very plainly, bear evidence of having been used. The tush is 

 much grown, with its outer surface regularly convex, and its inner concave, 

 the edges being sharp and well defined. The sixth molar is at its full 

 growth, and the third is shed to make room for the permanent tooth in its 

 place. These two kist-named teeth should always be examined in cases 

 where there is any doubt about the age. After five years, no further 

 shedding occurs in any of the teeth. 



The six- year-old mouth is the last upon which any great reliance can be 



