CLASSES OF CATERPILLARS. 43 
Mother, There is usually that num- 
ber, but I believe it varies in some species. 
When you find any caterpillars which 
have more than sixteen feet, you may be 
certain that they are the erucae of flies. 
Lucy. That is, you mean both the 
hard feet for crawling, and the soft feet 
reckoned together. 
Mother. Exactly. Caterpillars have 
been divided into classes by some natu- 
ralists, according to their habits of life^ 
or to their appearance. Here is a list I 
have written for you, that you may look 
over and remember them. 
The gregarious^ or those that live in 
societies. 
The solitary^ that live singly. 
The smooth. 
Those which are hairy all over. 
Those with the hair divided into little 
brushes. 
Hairy, but with longer brushes at the 
head and tail. 
The brushes forming a tuft^ or 
aigrette, on the head. 
