4-H CLUB INSECT MANUAL 



31 



Figure 76. — Syrphus fly. 



manure seems to be the preferred breeding ground, although the larvae 

 may be found in other decaying vegetation. Fly sprays will kill the 

 adults but they afford only temporary relief. 



Syrphid flies. — Another family of flies that are quite often found 

 hovering around flowers, or places where there is an abundance of 

 plant lice, is the syrphid flies, of which there 

 are a great many kinds. Although there is a 

 wide variation in these insects, many have de- 

 cided markings on the abdomen. The adults 

 of this group have two wings and sucking 

 mouth parts. These flies have complete life 

 changes. Some larvae feed on aphicls. One 

 would need to examine but few colonies of 

 plant lice before finding a very small, leg- 

 less, sluglike creature feeding on the lice. 

 This is the larva of the syrphus fly. These 

 flies remain over winter in the pupal stage 

 among leaves on the ground or on stems of plants. Since they are 

 beneficial, no control measures are necessary. The syrphus fly shown 

 here is Syrphus ribesii, which varies from three-eighths to one-half 

 inch in length. 



Flesh fly. — During the summertime any meat or dead animal will 

 draw a number of flies. Among the number will be found some that 

 are rather large, with black stripes on their backs 

 and their abdomens covered with hairs. Many have 

 red eyes. Like the other Diptera, the blowflies have 

 two wings. The adults feed upon carrion and flow- 

 ers, and the maggots upon meat. Some may be con- 

 sidered beneficial because the maggots help to de- 

 stroy dead animals; others are pests because they 

 feed on living tissue at open wounds and cause much 

 suffering, loss of flesh, and sometimes death of 

 animals. The pests can be controlled by good 

 animal-husbandry practices, but in some cases medi- 

 cation is necessary. These insects overwinter in the 

 puparium in the soil. The flesh fly here shown is 

 Sarcophaga plinthopyga. This species is from one- 

 fourth to one-half of an inch in length. 



Greenbottle flies. — Around meat or dead animals may also be 

 found a number of metallic, shiny, green or blue flies, slightly larger 

 than the housefly, the greenbottle or bluebottle 

 flies. These insects have lapping mouth parts and 

 two wings. They feed on carrion and flowers, and 

 overwinter in the puparium in the soil. They 

 have complete life changes. The larvae or mag- 

 gots feed on decaying meat and may be consid- 

 ered beneficial. In case the adults become pests, 

 they may be controlled by sprays and by burn- 

 ing or burying decaying meat or dead animals 

 so that breeding will not take place. The green- 

 bottle fly pictured here is Lucilia sericata; this 

 species is from one-fourth to three-eighths of an inch long. 



Figure 77. — Flesh 

 fly. 



bottle fly. 



