Life History of the Gypsy Moth. 



See Plate I. 



The gypsy moth has a complete metamorphosis. This means 

 that it has four stages in its life history — the egg stage; the caterpillar, 

 or active feeding, stage; the pupa, or resting, stage; and the adult, 

 or moth, stage. At the present writing the insect is found in the 

 caterpillar stage. The eggs are laid in clusters, containing from 

 three hundred to seven hundred eggs, on trees, shrubs, rocks, and 

 leaves; in fact on almost any object on which the female moth may 

 happen to be when ready to lay. The eggs are mixed with hairs 

 from the body of the mother insect and with a frothy glue which 

 make the clusters resemble a small piece of sponge. The clusters 

 are light yellow in color, oblong in shape, and from one-half to one 

 and one-half inches in length by from one-third to one inch in width. 

 The eggs begin to hatch in April and continue hatching through May. 

 At first the caterpillar is, of course, very small, and would be difficult 

 to distinguish from a great many others of different species. It 

 grows quite rapidly, and in nine or ten weeks reaches its maturity, 

 when it will be from one to one and two-thirds inches in length. The 

 caterpillar is covered with tufts of long hairs growing from projections 

 called tubercles along is sides and back. Its principal distinguishing 

 mark is the two rows of tubercles extending along its back. The 

 first five pairs of these tubercles are blue, and the six following ones 

 are red or crimson. At first the caterpillar feeds at all times of the 

 day. When approaching maturity, -however, it feeds during the 

 night and crawls into holes or crevices to rest for the day. When 

 mature, the caterpillar changes into a dark brown pupa. Pupae may 

 be found, in clusters or singly, attached to the bark of trees, to rocks, 

 fence posts, and other objects. Frequently clusters of these pupse 

 may be found accompanied by cast-off skins of the caterpillar, 

 empty pupa cases, and egg masses. The adult insect emerges in 

 about two weeks. The male is light brown in color, with dark 



