60 



ANIMAL DENTISTRY. 



molars and incisors alike. The first, second and third mo- 

 lars make the most rapid progress during the first year, pre- 

 paratory to their subsequent eruption one to two years 

 hence. The incisors are less developed, the centrals are 

 somewhat prominent preparatory to their eruption two years 

 hence, but the lateral, intermediates — in ruminants — and the 

 corners are merely represented by an undeveloped tooth 

 germ. Such is the condition of development of the denture 



Fig. 43. 

 Molars of a Horse Approaching 10 Months. 



of an herbivorous animal at the age of one year from whence 

 the evolution proper begins. (See Fig. 43.) 



THE HORSE. 



Central Incisor — Begins to develop in embryo, assumes 

 the shape of a tooth during the first year, reaches the level 

 of the alveolar border at two years, expels the temporary 

 shell at two and a half years and takes its place at the nor- 

 mal level of the arcade at three years of age. 



Lateral Incisor — Begins to develop during the first six 



