22 
THE CATERPILLAR. 
They can, however, hear, and that very quickly. 
A French naturalist made a number of experi¬ 
ments to ascertain the fact. He found that he 
could startle caterpillars by the sound of his voice; 
but not satisfied with this, he tried the effect of 
ringing a bell near to some that were moving 
quickly about. They instantly stopped, lifted up 
their heads and twisted them round, as if to ask 
what was the matter, or as if they were made 
uncomfortable by the sound. 
The caterpillar has two kinds of legs as well 
as of jaws, and its hinder legs are, in their 
way, great curiosities. Their principal use is to 
support the body by holding it firm to the branch 
or twig where the caterpillar is feeding; and they 
are as well adapted for this purpose, as the jaws 
are for satisfying its appetite. They are soft-and 
fleshy, and can be drawn in or out, so as to be 
made longer or shorter at pleasure. 
At the end of the leg is a foot, exactly fitted for 
the purpose of clasping the twig. The sole of the 
foot expands into a broad plate, that is furnished 
all round the edge with a row of hooks, one long 
and the next short, as you will see by looking at 
the picture. When the caterpillar stretches out 
its foot, these hooks lay hold of every little 
roughness or inequality, and enable it to cling 
to, what appears to us, a smooth surface. And 
