COVERING OP MAMMALIA. HAIR, QUILLS, ETC. 



the bottom than at the top ; they are frequently more or loss 

 flattened, and some are completely laminated, or pressed into 

 plates, like blades of grass. Sometimes their surface appears to 

 be perfectly smooth, and at other times it is fluted, or furnished 

 with little elevations, or else presents a bead-like appearance. In 

 short, their si/e, their shape, and their elasticity, vary greatly 

 among different animals, and even in different parts of the body 

 of the same individual. 



76. The name by which we distinguish the numerous varie- 

 ties of hair, differs according to the properties of these horny 

 filaments, and according to the parts on which they grow. Thus 

 they are termed prickles when they are very large, pointed, and 

 stiff, resembling spines (in the Porcupine and the Hedgehog for 

 instance) ; and bristles when they are smaller and less resisting, 

 but still very stiff, except to wards their extremity, as in the Hog. 



Fro. 47- PORCUPINE. 



Horse-hair only differs from Bristles, in being a little more 

 supple, and of smaller size ; in general it is, like them, quite 

 straight ; sometimes, however, especially when very long, it is 



