282 A MANUAL OF DENTAL ANATOMY. 



term canine ; but it should be borne in mind that its signi- 

 ficance is merely equivalent to " caniniform premolar," and 

 that in describing the dog's dentition (fig. 163) we should be 

 less liable to be misinterpreted, were we to say that it has 

 five premolars, of which the first is caniniform. To those 

 who accept the doctrine of evolution it is not needful to say 

 more, as it is hardly possible to resist the conclusion that 

 the teeth of the parent forms were, like those of the present 

 monophyodonts, not much differentiated from one another. 

 Then, as animals diverged and became modified in accordance 

 with their requirements, their teeth would become so far 

 differentiated that they would admit of being classified. 

 Thus the Carnivora would have attained to a stage of 

 differentiation in which the canine is functionally certainly 

 deserving of a distinction, whereas along other lines of 

 descent, differentiation having not proceeded so far, or having 

 proceeded in a somewhat different direction, it would not 

 merit a distinctive appellation. 



But as it so happens, that all the works on odontography 

 have started upon the basis that there was a " type " denti- 

 tion, and as a canine figured in that dentition, it will be 

 necessary to point out a few instances of the propositions to 

 which those anatomists are committed who call some tooth 

 a " canine " in every case where a tooth is situated in the 

 maxillary bone, close behind the suture which connects it 

 with the intermaxillary bone, whether that or any other 

 tooth be large and pointed, " caniniform " or not. 



In typical Ruminants, the upper jaw lacks both incisors 

 and canines (with certain exceptions, for which see p. 335), but 

 in front of the lower jaw there are grouped together eight 

 teeth, closely fitted together, and of almost exactly similar 

 size and shape. The outermost pair of these teeth are 

 called canines, because (i.) in some allied species the tooth 

 in this situation is more pointed; (ii.) because this tooth 

 shuts in advance of the upper canine when the mouth is 



