LEAF-EATING CATERPILLARS. 



183 



excrement being the only signs of their presence, 

 ment are often mistaken for 

 eggs, though caterpillars are 

 unable to lay eggs. 



The life history of these 

 insects is simple and can be 

 easily traced in captivity. 

 As a rule the parent moth or 

 butterfly deposits a large 

 number of eggs on the leaves 

 of the plants, often on the 

 under-surface, singly or in 

 clusters, but usually spread 

 over several plants. The eggs 



Such 



grains of excre- 



Fm. 210. 



Moth r>f common vegetdble-eating Caterpillar, 

 (Magnified three times,} 



Fm. 211. 



Moth of common leaf-eating Cater' 

 pillar of rice. 



are small and not noticed as they are 

 difficult to see. In the butterflies and 

 larger moths each egg is rounded, a little 

 flattened at the base and apex, adorned 

 with sculptured lines and ribs, In the 

 smaller moths, the eggs are commonly 

 flattened, oval in outline and very 

 inconspicuous. The eggs hatch in a 

 short time, usually less than a week, 

 into little caterpillars that crawl about 

 on the plants and feed first upon the 

 epidermis of the leaves. 

 "When grown larger they eat holes in the leaves or eat in from 

 the edge until the whole leaf is 

 devoured. They are voracious, a large 

 amount of plant tissue being con- 

 sumed which is only very slightly 

 digested and passes out of the body 

 as a little round grain of excre- 

 ment. Actually the greater part of 

 the food consumed passes through, 

 little more than the juice of the plant 

 being absorbed by the alimentary 

 canal. 



The first moult takes place in a 

 few days after hatching and succes- 

 sive moults occur until the cater- 

 pillar is full grown. Few of such 



FIG. 212. 



Pupa and moth of Caterpillar that eats 

 lilies. 



