SB 

 818 

 C578 

 ENT 



No. 39, Revised Edition. 



lited States Department of Agriculture, 



BUREAU OF ENTOMOLOGY, 



L. O. HOWARD, Entomologist. 



THE CO.MMON SC^UASH Mid. 



(AiKisii irislis DoCi.) 



By F. H. Chittenden, 

 In Cliarge of Breeding Kxperi)))ent^. 



GENERAL APPEARANCE AND METHOD OF WORK. 



The l)est known of all the insects which infest squashes and pump- 

 kins is the common squash hug, Anasa fristh DeG., otherwise known 

 as stink bug from its disagreeable 

 odor. It is also called black squash 

 bug to distinguish it from that other 

 enemj' of cucurbits, the so-called 

 " striped bug" {IHahrotica vittafd) . 



The species is a member of the 

 heteropterous family Coreidae. The 

 adult bug, shown at fig. 1, a, is of 

 large size, nearly three-fourths of an 

 inch long. It is dirty blackish brown 

 above and mottled yellowish be- 

 neath. Its wings, as with other 

 insects of its suborder, are folded 

 diagonally across its back, leaving a 

 large triangular space, the scutellum, 

 between 



haustellum or beak (see h) , by 

 means of which it sucks up the juices 

 of the plants on which it feeds. 



The sexes may be distinguishcMl by the external genital organs, r, of the 

 illustration representing the male and, d, the female. 



The injury wrought by this ))Ug is not coniined to squash and 

 pumpkin, although these plants, particularly the former, suffer most, 

 as records are not wanting to show at least occasional injury to oth(>r 

 cucurbits. This insect is more or less harmful during its entire active 

 existence, from the time it leaves the egg till its demise. When 

 numbers attack a plant together it is soon exhausted, and its death 

 often follows. It is a well-established fact that it is not alone the 

 extraction of the juices that destroys a plant, but that, whenever the 

 bug punctures or "stings" a leaf-stalk, it injects a drop of liquid, sup- 

 posed to be its saliva, which has a ])oisonous effect on the jilant, caus- 

 ing the death of the cell tissue about the i)uncture. Jt attai;ks also the 

 leaves and occasionally the fruit of cucan-bits. Still another form of in- 

 jur}^ is due to the insect's acting, although perhaps not to a very great 

 extent, as a transmitter of the insidious bactei'ial disease, lidcillKs fnt- 

 cheiphilns Erw. Sul 



On +Lf> 111-iflpi' eirip ia ifa t^u-. I.—A iidfia tn'sti/i: rt, mature female; &. side 

 KJU me unuei Slue is us ^.j^,^^. „,. ^^^,^^^ shouing haustellum; c. ab- 

 dominal segments of male: rf, same of fe- 

 male— n, twice natural size; b. c. rf, slightly 

 more enlarged (author's illustration). 



