8 MOTHS AND BUTTERFLIES. 
finds that they need bushels of fresh food daily when nearly full 
grown. Of course, in a state of nature the large larvee are usually 
widely scattered, so that their ravages are not so noticeable; but 
when feeding a large number hatched from eggs one is liable to find 
he has an elephant on his hands. 
A little protuberance under the mouth of the larva is the silk- 
spinning organ. This is the external opening to the silk secreting 
elands, which consist of two tubes or sacks, one on either side of the 
body, containing the viscid fluid which, by exposure to the air, dries 
and hardens into silk. This silk is used in a variety of ways by the 
different species of caterpillars. Some colonies build nests for their 
mutual protection; others attach a thin thread to the leaves and 
branches of the plants as they crawl over them, so that they are with 
difficulty shaken off, for they merely let themselves down on their 
threads a short distance and then crawl up again when the danger is 
past. Many species spin cocoons as silky coverings for themselves 
when they are about to pupate: and a good many of the butterfly 
larvee not only attach the posterior extremity of the abdomen to a 
silken carpet but anchor themselves with a strong cable spun about 
the body and attached to the substance from which they are sus- 
pended. 
If we examine a caterpillar, we shall notice that the first three 
pairs of legs, attached to the second, third and fourth segments 
Caterpillar of Butterfly. 
(calling the head the first), are different from the fleshy legs or 
claspers. These first six legs are hard and horny and provided with 
claws or hooks at the ends. ‘They are the true legs and correspond 
to the legs of the perfect fly. The usual number of claspers is five 
pairs, and these are placed on the seventh, eighth, ninth, tenth and 
