324 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



The species most commonly infesting our locust is tbe common Flesh- 

 fly {iSarcophaga carnaria L.), a wide-spread species and general scavenger, 

 common alike to Europe, America, and Australia, and probably to other 

 quarters of the globe. Its larvae infest different kinds of locusts and the 

 common Mantis ;* and they generally leave nothing but the bare shell of 

 their victim. They develop very rapidly; and, like the Tachina mag- 

 gots, burrow in the ground to go through their transformations.' The 

 accompanying figure of a variety {sarracenice Eiley), which feeds on the 



dead insects caught in those curious 

 traps, the Trumi)et-leaves (genus Sar- 

 racenia)^ will serve to illustrate these 

 transformations. 



Another species that attacks the 

 Eocky Mountain locust is the Calli- 

 pJiora erythrocepJiala, Meig., also very 

 common and wide spread, and easily 

 distinguished from the preceding by its 

 blue color. The foH owing extracts refer 

 to these flies : 



Fig. 62.— Saecophaga caenaria var. sarea- 

 CEM^. — a, larva; b, papa ; c, fly, the hair-lines" 

 shoT^ing average natural lengths ; d, enlarged 

 head and first joint of larva, showing curved 

 hooks, lower lip (g) and prothoracic spiracles ; 

 e, end of body of same, showing stigmata (/) 

 and prolegs and vent ; h, tarsal claws of fly, 

 with protecting pads ; i, antennae of same — en- 

 larged. (After Eiley.) 



than any other cause, so far as known. 



A certain bhie or green fly has been more 

 largely instrumental in destroying the insects 

 They operated by depositing an egg or eggs 

 about th« junction of the thorax with the abdomen, which produced a worm that 

 destroyed life in a short time. They were most active about the time of the second 

 molting. A few specimens of the flies (found dead) are forwarded. I also saw a 

 small spider destroy one, but cannot say whether many were killed in that way. — 

 [Daniel Parker, Calvert, Tex., April 26, 1877. 



During the summer I noticed that many of the large yellow grasshoppers (C«7opfe«?<s 

 differ entialis) were infested by the maggot of a species of fly very nearly resembling, if 

 not identical with, the common Flesh-fly (SarcojjJiaga carnaria). Many of the grass- 

 hoppers were almost completely eaten out when found, retaining just sufficient strength 

 to hop feebly ever the ground. I estimate that this particular species of grasshopper 

 was diminished in numbers at least one-tenth, possibly one-eighth, by these new 

 friends. It is to be hoped that these new parasites will increase rapidly. Professor 

 C. V. Riley informs me that the Migratory Locust {Caloptenus siwetus) is also infested 

 by a similar one. Thus far, however, I have failed to detect any in the specimens col- 

 lected in this vicinity.— [Professor C. E. Bessey, Ames, Iowa. 



As the young locusts began marching, swarms of green and blue flies made their 

 appearance, and seemed to accompany them. I soon found numbers of young locusts 

 dead with maggots in them, and supposed the flies were following them to blow those 

 accidentally killed, but during the second molt I discovered the locusts were very 

 tender and helpless, and I observed these flies watching them and alighting on them 

 as they came out of their casts. Catching one which I had observed attacked by the 

 fly, I found half a dozen live maggots busily engaged eating his entrails. By patient 

 watching, I found that those attacked by the fly would die in from five to ten minutes; 

 and the maggots, after finishing them, would disappear in the ground, and I suppose, 

 in the course of time, comes out a new fly. — [W. L. Coleman, Calvert, Tex., April 24, 

 1877. 



Ichneumon-flies. — It is an interesting fact that not a single Ichneu- 

 mon-fly is positively known to attack our locust, nor has one ever been foaud 



*" Locust Plague, etc., p. 13C. 



