108 



THE STRUCTURE OF THE HORSE 



These little rudiments of teeth, about which such non- 

 sense as the above has been written, are, when properly 

 understood, of intense interest. Their diminutive size, 

 their irregular form and inconstant presence, combined 

 with their history in the extinct horse-like animals, 

 show them to be teeth which, for some reason to us at 

 present unknown, have become superfluous — have been 

 very gradually and slowly (as in the case of all opera- 

 tions of the kind) dispensed with, and are, in the stage 

 to which the horse has now arrived in its evolution, 

 upon the point of disappearance. The presence of these 

 so-called 4 wolves' teeth ' alone is sufficient, if we had no 

 other proof, to show that the horse is not an isolated 

 creation, but one link in a great chain of organic beings. 

 The fact that these teeth are almost always met with in 

 the upper jaw only, should be noted in connection with 

 what has been previously mentioned respecting the 

 dentition of the tapir. The first upper premolar is 

 retained in that animal, while the corresponding lower 

 tooth has entirely disappeared. 



It would be very interesting, if a sufficiently large 

 number of specimens could be examined, to obtain some 

 statistical information as to the relative frequency of 

 the occurrence of these teeth in the different species of 

 wild and different breeds of domestic horses. They 

 are usually so loosely attached in the skull that they 

 become lost in specimens prepared for museums ; but 



