170 PHILOSOPHY OF ZOOLOGY. 



already been illustrated *. There is not in this tribe any 

 pouch connected with the mother, into which the expelled 

 fcEtus is deposited, as occurs in the marsupial animals. 

 The young of the placentular animals are more perfect at 

 their birth, and consequently less intimately dependent on 

 their mother. 



The animals of this division may be subdivided into ter- 

 restrial or aquatic ; two groups which are characterized by 

 remarkable conditions of their limbs. 



PEDATA. 



Char. — Skin with appendices in the form of ^hair, or 

 spines, or scales. 



Desc. — The posterior extremities are always developed, 

 and attached to the pelvis. Rest and sleep are enjoyed on 

 land, even in those species which seek their food in the wa- 

 ter. ^These pedate mammalia are either fingered or hoofed. 



UNGUICULATA. 



Char. — The four extremities terminating in fingers fur- 

 nished with nails or claws. 



This condition of the extremities, observed in the finger- 

 ed mammalia, gives them a capability of grasping objects, 

 of climbing, and burrowing, which the hoofed tribes do not 

 possess. In many of the unguiculata, the incisors exist in 

 one or both jaws, while in a small tribe they are wanting. 



1. Furnished with incisors. 



Those animals which have tusks are separated from such 

 as are destitute of them. 



• Vol. i. p. 40?. 



