ERUPTION OF THE PERMANENT OR ADULT TEETH. 75 



The time of the year and the race of the animal must be 

 taken into consideration in determining the completion of three 

 years. The better breeds of horses attain that age in mid- 

 winter, while those of more common races do not attain it until 

 the months of March, April, or May. 



Three Years Off. — When the colt is several months from 

 three years of age the permanent teeth are well used on their 

 borders and in contact with each other, but the dental cups are 

 not yet complete circles, as the enamel which forms them is still 

 connected with the peripheral enamel toward the borders of the 

 teeth. The intermediate teeth are very much worn, protrude 

 from the gums, and are sometimes broken and ready to fall out. 

 The tables of the corner teeth have become very much larger 

 and almost cover the external borders of the teeth. (Figs. 68, 

 69, 70.) 



Rising Four Years. — Eruption of the permanent inter- 

 mediate teeth and progressive falling out of the temporary inter- 

 mediate teeth mark this period. The permanent intermediate 

 teeth appear, but have not yet reached the level of the tables of 

 the corner teeth, and are not yet worn. The central enamel in 

 the pincher teeth surrounds the dental cup, which is flattened 

 from in front to behind, and is almost distinct. The corner 

 teeth commence to be free at their necks from the gums. 

 (Figs. 71, 72, 73.) 



Four Years. — Each jaw shows four permanent teeth, with 

 their tables on the same level ; the intermediate teeth are worn 

 both on their anterior and posterior borders, but the dental cups 

 are not entirely separated from the outside peripheral enamel. 

 Often the inferior pincher teeth are leveled, especially in well- 

 bred horses. The temporary corner teeth stand out from the 

 gums and are completely worn. (Figs. 74, 75, 76.) 



Four Years Off. — Loosening and successive falling out of 

 the temporary corner teeth, which are worn to stumps, scarcely 

 fastened in their alveolar cavities. Sometimes one or more of 



