60 



ANIMAL DENTISTRY 



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

 lars make the most rapid prog-ress during the first year, pre- 

 paratory to their subse(|uent 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 

 o-erm. 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 



