TYPICAL INSECTS 195 



a moment on a cabbage or nasturtium leaf, then doing the 

 same thing on another leaf, and so on. This is probably a 

 female laying her eggs. Watch the insect carefully, and, after 

 noting the leaf where she alights, examine for a minute the 

 yellowish egg placed upright on the surface. 

 Watch this egg for a few days, or cut off the leaf, 

 and placing it in a glass of water observe the 

 egg. It will soon hatch into a little green "worm" 

 or, more properly, a caterpillar, which imme- 

 diately begins to eat of the leaf on which it was 

 born. This caterpillar is the baby butterfly, very 

 different indeed from the beautiful winged form 

 of the adult. It continues to feed and grow, shed- 

 ding its skin periodically as it becomes too small, fig. 

 When full grown it is about an inch in length, and 

 is covered with short, soft hairs. The caterpillar is divided 

 into segments, but without any marked regional distinction. 

 On the sides of the segments may be seen the small breathing 

 pores. 



The head is small and mostly mouth, which is provided 

 with a pair of strong mandibles for biting and chewing. There 

 are no compound eyes, only several small, simple eyelets on 

 each side of the head. 



Examine the under side of the body. You will find on the 

 first three segments next to the head a pair of short, jointed 

 legs with clawed feet. These three segments correspond to 

 the thorax of the adult. There also seem to be legs on other 

 segments of the body; but closer examination will show that 

 they are not real legs, but fleshy, wart-like outgrowths of the 

 skin. They are called prolegs and are used for clasping. 

 At the end of the abdomen there is one pair especially used for 



