106 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



The maggots of several species of Tachina-flies arc of con- 

 siderable value in parasitizing both nymphs and adult locusts. 

 Their eggs are laid on the neck of a locust, and, upon hatching, 



FIG. 74. A Locust-mite (Trombidium locustarum): a, the larva as seen on 

 locust's wing; c, male mite; d, female, the two latter appearing as when 

 egg-destroyers all greatly enlarged. (After Riley.) 



the maggots pierce the skin and live inside by absorbing its 

 juices and tissues. When full grown the maggots leave the 

 locust, descend into the earth, and there transform to pupae 



FIG. 75. Anthomyia egg-parasite, a, fly; 6, puparium; c, larva; d, head of 

 larva. (After Riley.) 



inside of their cast skins, and from the pupae the adult flies 

 emerge in due time. 



The maggots of one of the Bee-flies (Systcechus areas) feed 

 upon grasshopper eggs, but their life history is not fully known. 



