44 2 



UNGULATES. 



THE PECCARIES. 

 Family DlCOTYLlD^. 



The peccaries, which are the American representatives of the swine, differ so 

 markedly from the latter that they are regarded as belonging to a separate family, 

 of which there is but a single genus. The most important differences between the 

 two groups are that the upper tusks of the peccaries have their points directed 

 downwards instead of upwards, that their hind-limbs have three instead of four 

 toes, while instead of the simple stomach of the Old World swine, the peccaries 

 have a complex one approaching that of the Ruminants. 



Peccaries have a total of thirty-eight teeth, that is to say, they have a pair of 



THE COLLARED PECCARY AND YOUNG (\ Hat. Size). 



incisors in the upper jaw, and a premolar on each side of both jaws less than the 

 wild boar. The downwardly-directed upper tusks, which are at first completely 

 covered with enamel, are of small size, with sharp cutting-edges behind ; while 

 those of the lower jaw are directed upwards, outwards, and slightly backwards, 

 and are received in notches in the sides of the opposite jaw just in front of the 

 upper tusks. The last molar tooth in each jaw lacks the hind lobe characteristic 

 of the Old World swine (see fig. on p. 421), and the fourth premolar tooth in the 

 upper jaw resembles the first molar in having four tubercles on its crown, instead 

 of only three. In addition to the difference in the number of toes in the hind-feet, 

 the peccaries are further distinguished by the upper ends of the two larger meta- 

 carpal and metatarsal bones being united, so that we have here an approach to the 

 formation of cannon-bones. In this respect, as well as in the complex structure of 

 their stomachs, and the presence of four tubercles on their last upper premolar 

 teeth, the peccaries are clearly one step in advance of their allies of the Old World. 



