185 



Ent., U. S. Dept. Agr., p. 91. 1903) have concluded that all the eggs 

 do not hatch with the first rain after their deposition, but that hatch- 

 ing is completed with the alternation of wet and dry weather. 



Mycetophilid^ 



Eiignoristc occidentalis Coq. 



A single specimen of this small fly was taken on the flowers of 

 Solidago (Sta. I) Aug. 12 (No. 26). The specimen was determined 

 by J. R. jMalloch. It had been previously recorded from goldenrod 

 flowers by Aldrich ('05, p. 148). 



Sciara sp. 



These small flies Avere taken from the flowers of the mountain 

 mint. Pycnanthcmum fle.vuosiim (Sta. l,g), Aug. 8 (No. 6). 



BOMBYLIID^ 



'Exoprosopa fasciafa IMacq. Giant Bee-fly. 



This was one of the most abundant and characteristic insects of 

 the prairies 'and cleared areas, and belongs in the same class as the 

 red milkweed beetle (Tetraopes) and the milkweed bug. Lygcrus kal- 

 iin'i. It was taken from flower masses of the mountain mint Pycnan- 

 thcmuin flexiiosum. (Sta. I, g) Aug. 8 (No. 6); on the flowers of 

 Verbena stricta Vent, (near Sta. I, a) Aug. 11 (No. 23) ; again from 

 P. flexnosuin (Sta. I) Aug. 11 (No. 24); and on the flowers of 

 Liatris seariosa (Sta. 11, a) Aug. 27 (No. 176). Two specimens 

 had been captured by the flower spider Misiimcna aleatoria Hentz : 

 one on flowers of the rosin-weed, Silpkimn integrifolhnn (Sta. II), 

 Aug. 13 (No. 47), the other on flowers of the mountain mint Pycnan- 

 themmn fiexuosinn (Sta. I) Aug. 12 (No. 31) ; and a third was cap- 

 tured bv the ambush bug. Phyniafa fasciata Gray, on the flowers of 

 the mountain mint (Station II) Aug. 13 (No. 57). 



This was a very common species on the prairie patches at Bloom- 

 ington. 111.. July 26 to Aug. 23, and in pastures abounding in Verbena 

 at Kappa, 111., and Havana, III, in August. Graenicher ('10, pp. 94- 

 95) has listed several species of flowers from which this fly has been 

 taken. It is probable that it preys upon some wasps, since a related 

 species. E. fascipeunis Say, has been bred from the cocoons of the 

 white-grub wasp, Tiphia (Forbes, '08, p. 160). 



Sysfaxhiis vulgaris Loew. 



In the cleared area bordering the Bates woods, on flowers of the 

 mountain mint Pycnanthemmn pilosum (near Sta. IV, a), a specimen 



