HISTORY OF THE CARNIVORA 555 



IV. tOXYiENIDiB. 



'\ PalcBonictis, low. Eoc. jOxyoena, do. f Patriofelis, mid. Eoc. 

 ■\Limnocyon, do. fMachair aides, do. '^Oxywnodon, up. Eoc. 



V. tHY^NODONTIDiE. 



t(Si?M)pa, mid. Eoc. ^ Stypolophus, low. and mid. 'Eoo. ^Tritemnodon, 

 mid. Eoc. j Pterodon, low. Oligo. f Hycmodon, do. 



VI. tMlACIDiB. 



^Didymictis, Paleoc. and low. Eoc. ^Viverravus, mid. Eoc. ^Mia- 

 ds, low. Eoc. ^TJintacyon, low. to up. Eoc. \Oddectes, mid. Eoc. 

 \Vvl'pavus, do. f Palceardonyx, do. 



The fCreodonta were an extremely varied assemblage, of 

 carnivorous, omnivorous and presumably insectivorous habits, 

 so that few statements, not subject to exceptions, can be made 

 of them all. Only seven genera are known from skeletons, and 

 several more from skulls, but most are represented only by jaws 

 and teeth ; limb- and foot-bones, however, give us a conception 

 of the general structure of a considerable number. As a 

 rule, the dentition was complete, according to the formula, 

 * I) c y, p f , TO f , X 2 = 44, but the first premolar or the last 

 molar may be lost. The canines were always large, as was be- 

 fitting for beasts of prey. In only one family, the Miacidae, 

 were the carnassial teeth confined to a single pair and those 

 the same as in the Fissipedia, the fourth upper premolar and first 

 lower molar; in all the other famihes there were either no 

 sectorial teeth, or else there was more than one pair. In the 

 Fissipedia the first is the largest of the lower molars, while in the 

 fCreodonta (except the fMiacidse) it was usually the smallest. 

 The premolars were generally simple, compressed-conical teeth 

 and the molars, with all their great variety, may be reduced to 

 a common plan ; those of the upper jaw were primitively tri- 

 tubercular, with a triangle of two external and one internal 

 cusps, and those of the lower jaw were in two distinct parts, 

 an anterior, elevated triangle of three cusps and a low heel 

 of two. 



The skull was almost always very large in proportion to the 

 size of the animal ; the cranium, though long, was of small 



