THE. TUSHES, TUSKS, CANINE TEETH. 



31 



become worn down, until they assume a parallel position, and 

 finally converge, instead of diyerging, at their free extremities. 

 The intermediate teeth become separated from the pinchers on 

 the one side, and the corner teeth 

 become separated from them on 

 the other, until a distinct space 

 is yisible between them, which is 

 filled by a pale gum. 



En resume in regard to the 

 general direction of the incisors : — 



1. The . incidence of the 

 arches acquires a greater obliquity 

 with age. 2. Their incurvation 

 and their transverse diameter di- 

 minish. 3. The teeth, at first di- 

 verging from their roots, become 

 parallel and finally converge 

 toward their free extremities. 



THE TUSHES, TUSKS, CANINE TEETH. 



The tushes are four in num- 

 ber in the adult horse ; they are 

 rudimentary or absent in the 

 mare. In certain sections of the 

 country superstition has attributed 

 sterility to mares provided with 

 them, which is, however, abso- 

 lutely unfounded. 



The superior tusks are placed 

 one on each side of the upper in- 

 terdental spaces, at the point of 

 union of the superior maxillary 

 and intermaxillary bones. The lower ones are placed on either 

 side of the maxilla, always closer to the incisor teeth than those 

 of the upper jaw, so that they are invariably in front of the latter. 



The canine teeth are curved in their long axis with the 



Fig. 18. 

 Incisors of the two jaws (roots un- 

 covered), seen by their anterior face to 

 show their direction in regard to the 

 median line. 



