127 



The presence about the breeding jars of flies belonging to species of 

 Sarcophagidee was frequently noticed throughout the summer, but only 

 once were any adults bred from jars containing bollworms. In this 

 case some living pupae had been buried in finely sifted earth in a glass 

 jar covered with cheese cloth to determine the ability of the emerging 

 moths to pass through a stratum of loose soil. One morning after 

 several moths had appeared, three small specimens of Helicobia helicis 

 Town, appeared also. On exhuming the remaining pupse the fly 

 puparia were unearthed close to an empty boUworm pupa case. 

 Whether the eggs of the fly were in the soil, whether they were laid 

 through the cloth, or whether the eggs or young larvae were already 

 on one of the live pupae, would be impossible to say. Hubbard^* 

 records an almost exactly similar instance. Whether this is a case of 

 true parasitism remains very doubtful. 



Larvae of another fly, Euxesta annonde Fab. , were obtained by Mr. 

 Jones at Wharton, Tex., on July 20, 1904, feeding on the juices of a 

 dead bollworm, and from them adults were bred out in the laboratory. 

 The flies are often to be seen about corn plants during the earlier part 

 of the season, and no doubt their larvae also feed on decaying vegeta- 

 ble matter, like the other species of the genus. 



The other small muscid flies, Drosophila lyunctxilata Loew and D. 

 ampelopliila Loew, were bred from cotton bolls decaying as the result 

 of bollworm injury. 



Monocrepidius vespertiniis Fab. and another larger click beetle also 

 act as scavengers after the bollworm. 



A small nitidulid beetle {Ooiiotelus obscicrus Er.) is very common in 

 ears of corn which have been previously injured by the bollworm. 

 In a badly damaged ear often as many as thirty or forty of these 

 little black beetles may be present when the corn is nearl}^ ripened. 

 The}^ do not attack the corn unless it has been already injured by 

 the bollworm. Several other species of Nitidulidae also frequent the 

 damaged ears and bolls. 



METHODS or BOLLWORM CONTROL. 



CULTURAL METHODS. 



By reason of its feeding habits, the control of the cotton bollworm, 

 as compared with many insects, presents unusual difiiculties. On cot- 

 ton, corn, and tomatoes, particularl}^, it feeds on the interior plant 

 tissues, and is therefore not amenable to such insecticidal treatment as 

 is effective for many related species. Further, it is much less subject 

 to the attack of parasitic and predaceous enemies than insects feeding 



« Fourth Rept., p. 110, 

 22051— No. 50—05 9 



