24 VETERINART DENTAL SURGERT. 



Permanent incisors are convex anteriorly, the lower 

 incisors have one, the upper, two grooves down the 

 center of the body. These are filled with cementum, 

 but are absent in old teeth. 



[*"The follicle in which the incisor teeth are de- 

 veloped shows only two papillae; one for the secretion 

 of the dentine lodged in the internal cavity of the 

 tooth, and hollowed into a cup-shape at its free ex- 

 tremity. The other is contained in the external cul- 

 de-sac (Fig. 5, A. B. c.")]. 



The tushes, tusks or canine teeth, well developed 

 in dogs and other carnivora, are simple teeth, four in 

 number, two above and below. They rest in the in- 

 terdental spaces, the lower being nearer the incisors 

 than the upper ones; they are permanent and appear 

 between the fourth and fifth year, sometimes a year 

 in advance. The crown is somewhat conical, the base 

 being at the gums. The external surface is convex 

 and marked by several longitudinal lines; the internal 

 surface presents on either side a sharp ridge, which 

 separates it from the external. The crown ter- 

 minates in a conical eminence; somewhat hollowed 

 internally during growth, and bounded by a sharp 

 ridge. When a tusk has been long in wear, the ridge 

 disappears, and the internal surface becomes nearly 

 smooth, and as the apex of the tooth becomes worn 

 away, often a small mark appears but no second ring 



*Chauveau . 



