GROWTH AND TRANSFORMATIONS OF INSECTS 51 



lighter crimson, and the posterior thorax and abdomen a bright 

 green ; but in an hour the crimson darkens, and in a few hours 



changes to a jet- 

 black. The young 

 bugs hatching from 

 a cluster of eggs 

 remain together in 

 a sort of family dur- 

 ing their infancy, 

 each inserting its 

 tiny beak in the 

 succulent leaf from 

 which it vigorously 

 sucks the juice. In 

 about three days 

 the abdomen be- 

 comes distended, in- 

 dicating the need of a larger suit of clothes to allow further 

 growth. The nymph now assumes a quiet position, the skin splits 

 down the middle of the back 

 along the thorax and anterior 

 abdomen, and gradually the little 

 bug pulls itself out of its baby 

 clothes, the time required for 

 this change of costume vary- 

 ing from a half-hour to several 

 hours. A few hours later the 

 skin, now much lighter in color, 

 has hardened, and the insect is 

 about one fifth inch long. The 

 nymph now becomes more active 

 and alert and continues to feed 

 some nine days before molting 



FIG. 63. Egg masses of squash-bug. (Twice natural size) 

 (Photograph by R. I. Smith) 



FIG. 64. Squash-bug 



a, mature female ; t>, side view of head, show- 

 ing beak ; c, abdominal segments of male ; 

 d, same of female, (a, twice natural size ; 

 , <:, d, more enlarged.) (After Chittenden, 

 United States Department of Agriculture) 



again. In the third stage it is 



considerably larger and flatter, 



and darker in color. Eight days 



later the third molt takes place, and the new clothes of the fourth 



stage differ in having small but distinct wing pads extending back 



