BUTTERFLIES AND MOTHS 25 



Many of the worms that damage our trees and crops are cater- 

 pillars. In order to find out what kind of butterfly or moth 

 they become you have only to shut them up until they change 

 to full-grown insects. 



Web Worms. — Some kinds of caterpillars spin dense webs 

 in which they live at night and on damp days. You may often 

 see their webs on fruit trees, where the caterpillars sometimes 

 stwip the limbs bare of leaves. 



How to raise Caterpillars. — Shut the caterpillars in a lamp 

 chimney, fruit jar, or small box. Cover the top or sides with 

 mosquito netting to let in air. Feed the caterpillars with 

 leaves from the same kind of plant that they were on when 

 you found them. Take away the old leaves, and put in new 

 ones every day. Keep the cage clean, for caterpillars natu- 

 rally live on clean plants and in fresh air. Give the caterpil- 

 lars a little care each day. They will thrive and soon undergo 

 a wonderful change. 



2. THE PUPA 



When a caterpillar reaches its full size, it sheds its 

 skin and becomes a pupa which looks entirely differ- 

 ent from the larva. It remains motionless for a few 

 days or weeks while further changes take place that 

 make it a winged creature. 



Observation. — How long did you keep the cater- 

 pillar before it changed to a pupa ? In what part of 

 the cage did it go to become a pupa ? Look carefully 

 at the pupa to see how it is held in its place. What 

 is the size of the pupa that you observed ? What is 

 its shape ? What is its color ? Touch it to find out 

 whether its shell is hard or soft. Does it move at 



