THE SqUASH BUG 1 7 



egg shell, near one end and a little above the middle, is pushed 

 out, and the insect emerges through the opening thus made. 

 That there is some provision in the structure of the shell for 

 the breaking off of this disc is evident from the perfect appear- 

 ance of all the discs. In some cases that were observed in 

 hatchitig, both in the field and in the laboratory, the fore legs 

 were free ; while in about as many others these legs, like 

 the rest of the appendages, were snugly folded to the body, 

 becoming free only when the insect was entirely out of the 

 shell. 



The newly-hatched squash bug is more brilliantly colored 

 than at any other time during its life, and these colors make it 

 very conspicuous against the green background of the leaves. 

 The color of tlie abdomen and the posterior portion of the 

 thorax is light green ; that of the legs and "• feelers" or an- 

 tennae, a beautiful crimson ; that of the head and anterior 

 portion of the thorax a lighter crimson, while the margins of 

 the eyes are darker. This beauty, however, is but short-lived ; 

 at the end of an hour the crimson is noticeably darker, and in 

 a few hours it changes to a jet black. 



The young squash bugs soon begin their attack upon the 

 plant by inserting their tiny beaks in the succulent tissues of 

 the leaves. In their general habits they resemble the adults 

 After about three days of this feeding, the abdomen becomes 

 noticeably swollen and the color somewhat lighter. This is 

 an indication that the period of moulting has arrived. 



The young nymphs now assume a quiet, stationary attitude. 

 The process of moulting begins by the splitting of the skin 

 longitudinally along the middle of the upper surface of the 

 body, the split extending along the thorax and the front end 

 of the abdomen. The time required to complete this opera- 

 tion varies greatly : in the field the sliortest period we have 

 observed was thirty-two minutes, while in the laboratory six 

 hours have sometimes been required. 



A few hours after the first moult when the bugs have taken 

 on their normal colors they are considerably lighter than they 

 were before. The length is now about 1-9 inch. They are 

 also more alert, moving about more rapidly. They feed 

 again upon the sap of the leaves for about nine days when 



