30 APPEARANCE OF THE LARVAE. 
Mother, None of the hairy kinds go 
into the ground : those which burrow 
are smooth ; and as the ground is always 
rendered less hard or compact by the 
slender fibrous roots of plants, they can 
readily make their way into it. 
Several species of caterpillars have so 
much the appearance of the substances 
on which they feed^ that it is difficult to 
distinguish them. 
Lucy. But how can they look like 
leaves ? 
Mot1ie7\ It is not in shape but in 
colour that the resemblance to leaves 
consists, having sometimes their exact 
shade of green or of brown ; other kinds 
are so like the small branches upon 
which they are found, that you might 
easily mistake them for the short twigs. 
Some of them are quite smooth, like the 
twigs of the plane tree ; and some are 
marked lengthways with dark streaks, 
resembling the shoots of the elm. Thus, 
you see, many must avoid being disco- 
vered by their pursuers. But some spe- 
