CARNIVORA. 



GIB 



vegetable feeders. The dentition though essentially similar 

 throughout the group shows some variation which is generally 

 correlated with the mode of nutrition, though in the case of 

 the bears it would be difficult to distinguish the carnivorous 

 forms from the frugivorous by this character alone. 



The essential features are as follows : six incisors (very 

 rarely fewer) in each jaw, conical or chisel-shaped, set nearly 

 in a straight line across the jaw and usually increasing in size 

 from within outwards ; two powerful pointed canines pro- 

 jecting beyond the other teeth ; a variable number of grinders 

 divided as 



usual into ^ ^~~* x 

 premolars . 

 which have 

 predeces- 

 sors in the 

 milk denti- 

 tion, and 

 molars. 

 The lower 

 canines 

 bite in 

 front of 

 the upper, 

 which are 

 separated 

 from the 



incisors by a small gap. One of the grinding teeth on each side 

 in each jaw is different from the rest and called the carnassial 

 or sector ial tooth. In the upper jaw the tooth so modified 

 is p 4, in the lower jaw m 1. The teeth in front of the 

 carnassial are sharp and compressed, those behind it as a 

 rule are broad and tuberculated. The former consist of a 

 main cusp to which is frequently added a small anterior and 

 posterior cusp. The carnassial tooth of the upper jaw (p 4) 

 has when typically developed, an elongated trituberculate 

 crown and three roots (Fig. 322, //). Two of these tubercles 

 (2, 3), of which the anterior (2) is the longer, may be said to 

 constitute the outer blade of the tooth, while the third is 

 low (4) and forms a talon-like process at the anterior end of 



FIG. 322. Left upper carnassial teeth / of Felis, II of Canis, III of 

 Ursus, seen from the outer side and from below (from Flower 

 and Lydekker). 1 anterior, 2 middle, 3 posterior cusp of the 

 blade, 4 inner cusp of the upper carnassial, supported on distinct 

 root, 5 inner cusp posterpr in position and without distinct root, 

 characteristic of the Ursidae. 



