288 



ANATOMY OF VERTEBRATES. 



of the sense of touch through the greater number and mobility 

 of the digits, and the smaller extent to which they are covered 

 by horny matter. This substance forms a single plate, in the 

 shape of a claw or nail, which is applied chiefly to one of the 

 surfaces of the extremity of the digit, leaving the other, usually 

 the lower, surface possessed of its tactile faculty, fig. 170; whence 

 the name Unguiculata, which, in the present classification, is re- 

 stricted to this group. All the species are ' diphyodont,' and the 

 teeth have a simple investment of enamel. 



170 



17 



Unguiculate limb, Lion. 



Carnivorous dentition, Bear. 



The first order, Carnivoea, includes the beasts of prey, pro- 

 perly so called. With the exception of a few Seals, the incisors. 



^g, 171, z, are o^q in number; the canines, ib. 



■i i_p 



always 



longer than the other teeth, and usually exhibiting a full and 

 perfect developement as lethal weapons ; the molars, ib. p, m, 

 graduate from a trenchant to a tuberculate form, in proportion as 



172 



173 



\ J 



rimiigrade foot : Hind limbs. Seal. Bones of do. 



the diet deviates from one strictly of flesh to one of a more mis- 

 cellaneous kind. The clavicle is rudimental or absent ; the inner- 

 most digit is often stunted or absent; there are no vesiculte 

 seminales ; the teats are abdominal ; the placenta is zonular. The 

 Carnivora are divided, according to modifications of the limbs, 

 into ^ pinnigrades,' ^ plantigrades,' and ' digitigrades.' In the 



