6S2 AN INTRODUCTION TO ENTOMOLOGY 



The gypsy moth, Porthetria dtspar. — This is a European species 

 which was introduced into Massachusetts in 1866 by a French 

 naturahst who was conducting experiments with silk-worms. Some 

 of the insects escaped from him into a neighboring woodland and be- 

 came established there; but they did not attract particular attention 

 till about twenty years later. It was then realized that this species 

 is a serious pest. Since then millions of dollars have been expended by 

 the State of Massachusetts and the Federal Government in an un- 

 successful effort to exterminate it. It has spread over a large part 

 of New England, and isolated colonies have been found in New York. 



The larva has a wide range of food- 

 plants, feeding on the foliage of 

 most forest and fruit trees. The 

 male moth is yellowish brown; the 

 female white (Fig. 852). In each 

 the fore wings are crossed by many 

 dark lines and bear a black lunule 

 on the discal vein. The specimen 



figured is unusually small. The eggs 



Fig. S52.— Porthetria dispar. are laid in a mass on any convenient 



object and are covered with hair 

 from the abdomen of the female. The larva differs greatly in appear- 

 ance from those of the preceding genera, lacking the peculiar pencils 

 and tufts of hair; but the characteristic glands of the sixth and 

 seventh abdominal segments are present and are red. The body is 

 dark brown or black, finely reticulated with pale yellow, and with 

 narrow yellow dorsal and subdorsal lines. On the dorsal aspect of 

 each segment there is a pair of prominent, rounded tubercles bearing 

 spiny black hairs. The first five pairs of these tubercles are bluish, 

 the others dark crimson-red. There are also two rows of tubercles 

 on each side of the body which bear longer hairs. 



The brown-tail moth, Euproctis chrysonhcea. — The brown-tail 

 moth is another European pest, which was introduced into Massa- 

 chusetts at some unknown date. It first attracted attention by its 

 ravages in 1897, and since then has spread over a considerable part of 

 New England and has extended into New Brunswick and Nova Scotia. 

 The wings of the female moth are white; and the tip of the abdomen 

 bears a tuft of yellowish brown hairs, hence the popular name of the 

 insect.' The female expands about 37 mm. The male is a little 

 smaller than the female; and the brownish tuft at the end of the 

 abdomen is not so conspicuous as in the female. The larva feeds on 

 the foliage of fruit-trees and of almost all kinds of shade-trees except 

 conifers. The eggs are laid in an elongate mass on the underside of 

 a leaf, during July. The egg-mass is covered with brownish hairs 

 from the tip of the abdomen of the female. The eggs hatch in two or 

 three weeks. The larvae hatching from an egg-mass feed together on 

 adjoining leaves at the tip of a branch. These they web together with 

 silk, making a nest within which they pass the winter in a partially 

 grown condition. In early spring the larvee leave their winter quar- 



