CARNIVORA. 



449 



crolestes of the Upper Trias be Marsupial, as is almost certainly 

 the case, then the order Carnivora is comparatively modern, the 

 earliest undoubted remains having been found in the Eocene 

 Tertiary. In the Eocene period, however, the families of the 

 Canidce and Felidce appear to have been already differentiated. 

 The Ursidce, Viverrid(z,Mustelidce,Hy<znidcz, and Phocidce, do not 

 seem to have made their appearance before the Miocene period. 

 In the Pliocene and Post-Pliocene periods almost all the existing 

 types of the Carnivora are represented by extinct forms, whilst 

 in the latter the remains of various living species are found 

 associated with other animals which have at the present day 

 entirely passed away. In the following are given the charac- 

 ters and chief fossil forms of the families of the Carnivora. 



Fig. 366. Feet of Carnivora (after Owen). A, Plantigrada, Foot of Bear ; 

 B, Pinnigrada, Hind-feet of Seal; C, Digitigrada, Foot of Lion. 



SECTION I. PINNIGRADA. This section of the Carnivora 

 comprises the amphibious Seals and Walruses, which differ 

 from the typical Carnivores merely in points connected with 

 their semi-aquatic mode of life. The body is elongated, some- 

 what fish-like in shape, and terminated by a short conical tail. 

 All the four limbs are present, but they are very short, and the 

 five toes of each foot are united by the integuments, so as to 

 form powerful swimming-paddles. The hind-feet are placed 

 very far back, their axis nearly coinciding with that of the body 

 (fig. 366, B). Owing to this circumstance the hinder end of 

 the body forms an admirable swimming apparatus, similar in 

 its action to the horizontal tail-fin of the Cetacea and Sirenia. 

 The tips of the toes are furnished with strong claws, but the 

 powers of terrestrial locomotion are very limited. The ears are 



2 F 



