346 THE HIND FOOT OR PES. ICIIAI-. 



occurs in the Galagos and certain other Lemurs, owing to 

 the modification of two bones, the calcaneum and the navi- 

 cular; the distal portion of the former, and the whole of 

 the latter, having the form of nearly cylindrical rods placed 

 side by side, while the other bones retain nearly their normal 

 form and proportions. A precisely similar modification is 

 carried to a still greater extent in the genus Tarsius (see 

 Fig- 123, p. 345)- 



All the terrestrial CARNIVORA have the normal number of 

 tarsal bones, with very little deviation from their normal 

 form and relations. 



The hallux is present and well developed, though shorter 

 than the other toes, in the Ursidce, Procyonidce, Mustelidcc, 

 and most of the Viverridce. In the Canidce, Hycznidce, and 

 Felidtf, it is only represented by a rudimentary metatarsal. 

 The other four metatarsals and digits are always well de- 

 veloped and subequal. The lingual phalanges in the Felida 

 present the same characters as those of the fore limb (see 

 p. 288). 



In the Bears, the foot is flat, broad, and plantigrade. In 

 the Dogs and Cats, it is longer and narrower, and the heel 

 is raised from the ground in walking. 



In the Sea Otter (Enhydra)^ the hind foot approximates 

 to that of the Seals. It is very large and flattened, almost 

 fin-like, and much everted ; but the hallux is still shorter 

 than any of the other digits, and the two outer toes are the 

 longest. 



In the Seals the pes is completely modified for a special 

 purpose. It has no longer any function as an organ of 

 support or progression on land, and is habitually directed 

 backwards, with the dorsal surface outwards, and the 

 plantar surface in contact with the corresponding part of 

 the opposite limb. The calcaneum is very short, its tube- 



