No. 6. DEPARTMENT OF AGRICULTURE. 533 



habits as the first brood. In the northern part of the United States 

 there is but one brood. When the weather is cool they go under 

 cover for protection, and come out into the sunshine to be warmed. 

 (Fig. 10.) At night they seek the cover of a leaf, the under side of 

 a board, etc. (See Fig. 44.) This habit leads them to their diestruc- 

 tion where board traps are used. (See Mechanical Device No. 4.) 



In the fall of the year the insects are quite likely to collect on the 

 green fruits of the vine and suck juices from them after they can no 

 longer derive any from the leaves. This is the time that they should 

 especially be killed by kerosene spray or sprinkling to prevent their 

 scattering and living through the winter to become the progenitors of 

 of next year's pests. 



As the broods are not sharply separated, but some individuals lay 

 early ani others lay later and the laying and hatching continues 

 throughout the season, all stages can be found at one time, and there 

 is the appearance of continuous breeding. (Fig. 11.) 



The winter is passed in hibernation in the adult stage, sometimes 

 far away from the places where the infested plants grew. They 

 hibernate in woods, along fences, in rubbish, under boards, espe- 

 cially in lumber piles, in grass, sod, etc. On account of their offen- 

 sive odor they have no conspicuous vertebrate enemies, such as 

 snakes, toads, birds or skunks, as have many other species of insects, 

 but they are greatly infested with the larvae of parasitic flies 

 {Tachina). When the bugs become abundant, as in the summer of 

 1901, these parasitic flies multiply in the first brood and become so 

 numerous in the second brood as to materially reduce the number of 

 adults going into hibernation. In fact last fall we could not find one 

 adult that did not have upon its body one or mbre eggs or parasites 

 (Fig. 12) and under or near these empty egg shells there could be 

 found the tiny hole where a young fly larva had bored into the interior 

 of its host. Owing to this fact we then predicted that there would 

 be but few squash bugs during the season of 1902, and this prediction 

 was fulfilled to a remarkable degree. 



REMEDIES. 



Since these are sucking insects and do not bite the plants, they 

 cannot be killed by poisons. The only remedies that can be effect- 

 ively employed against them are clean farming, hand-picking, me- 

 chanical contrivances (Nos. 1, 2 and 4, described later), contact sprays 

 and painting the eggs with something like pitch to destroy them. 



To prevent next year's brood it is important that the vines be de- 

 stroyed and the green fruits be removed just as early as possible in 

 the fall. If this were universally done there would be no bugs of 

 the eeoond brood coming to maturity. 



