ANIMAL DENTISTRY. 75 



molars in each arcade, the first second, and third. The 

 crowns of the incisors are short and contact only at the 

 anterior margin. The infundibula are wide, elliptical and 

 deep, and their posterior boundaries are buried within the 

 gums. At one month the posterior edges of the infundibula 

 are exposed and the lateral incisors are breaking through 

 the gums. Two weeks later their crowns answer the same 

 description as the centrals at birth. During the next eight 

 or nine months there is no great change in the arcades ex- 

 cept the elongation of the crowns, which resemble a cone 

 broken off at its apex. The tenth month is marked by the 



I 



Fig. 47a. 

 Inferior Incisors at Birth. 



eruption of the corner incisors and the fourth permanent 

 molars. 



FROM ONE TO TWO AND A HALF YEARS. 



The absence of any prominent event during this period 

 makes the determination of age rather difficult. The incisor 

 teeth become large and prominent in all the features of 

 teeth, and are not easily recognized from permanent teeth. 

 If unassisted by the colt-appearance of the subject the mouth 

 during the last part of this period is readily mistaken for a 

 full mouth of permanent incisors. When any doubt ex- 

 ists the examination of the molars will reveal the presence 

 of but four teeth in each arcade. At the age of two to two 

 and a half years the fifth molar will be found breaking 

 through the gums. The incisors are white, have a some- 



