4-2 THE ORTHOPTERA OF MIXXESOTA. 



of futiire organs. If fully grown the maggots force their 

 WET through the skin of their host and drop to the ground. 

 Here thev burrow in the earth, and, contracting into brown 

 barrel-shaped puparia, they rest awhile. 



Inside this puparium, composed of the old larval skin, 

 the true pupa is formed, and later the winged fly, which 

 breaks through the surrounding skins and crawls towards 

 the light of day. In a very short time it is able to use its 

 wings, and is ready to enjoy life after its own fashion. A 

 locust harboring such a maggot, or several of them, is less 

 active than others, and seems to look upon life as a rather 

 serious afl'air, in fact to think it a real bore. Fishermen in 

 search of bait catch such languid locusts much more readily 

 than health V ones, but tind. in pulling away their wings or 

 heads, a humane way that disciples of Isaac Walton have, 

 nothing but an almost empty shell, by no means a tempt- 

 ing morsel for a fish. Several species of Tachina-flies infest 

 locusts. 



Flesh-Fly. — [Sarcophaga carnaria Linn.), a well 



known scavenger in Europe, 

 »:^- ,1^ ^^^^^k^ J\ Australia and America, is 



also found as a true parasite 



in many species of locusts. 



It, as well as its earlier 

 ==^ y^y?7^ t// J^ \->^ stages, are illustrated in 



Fig H.—Sarcopbaga caraaria var.— a, p-,,. -j 4 This illuStratioU 



lai-ia; b. pupa; c. flv. the hair lines show- ^^&- -^*- ^ ^^* iiiusLi ct nvjii 



ing average naturallength. (After kiley). ^^.-j^ ^j^^ ghowthe shapC, 



size and general appearance of a true tachina-fly, which 

 is quite similar to it. 



Bee-Fly. — (Systoechus oreas). When fields, meadows 

 and pastures are inspected for the eggs of locusts the 

 larvffi of these flies are always found, showing that these 

 friends of the farmer are doing good work. The adult 

 fly is illustrated in Fig. 15, the larva in Fig. 16. The 

 beautiful flies are frequently seen towards the middle of 

 Jiflv; thev are then employed in sipping honey with their very 



