251 



PsUocephala htrmorrhoiihdls Macq. 11.2, 4; Je. 6, Au. 18. (2) 

 Resting on bare sand. 111. 



Laphystia 0-fasciata Say. H.2, 4; Je. 0, 7. (2) On the bottoms 

 of deep blowouts in company with Microhembex monodonta, 

 which it somewhat resembles, especially when in action. No 

 other Illinois records; Common at the seashore. (Note 17) 



Dasyllis gvosxa Fabr. H.4, July 1. No other Illinois record. 



Proctacanthus hrev'qyennis Wied. H.l, 2, 4; Je. 6, 7, 8, 23. (6) 

 Flying about vegetation in sandy places, and alighting on or 

 near the ground. No other Illinois records. These "robber- 

 flies" ijrey on other insects. 



rroctacanthus m/lbertii Mac<i. H.2, 3, 4; Au. 15, 18, 19, 20. (9) 

 With the preceding species; said to prey upon honey-bees 

 and grasshoppers. Sand ridges near L. JMichigan, Waukegan. 

 AsilU'S ayrion. Jaennicke, a doubtful synonym, is the only 

 other record for Illinois. 



Erax lestuans Linn. H.l, 4; Je. 6, 7. (8) Common along sandy 

 roads near the Devil's Neck. La Salle Co., Mt. Carmel, Ur- 

 bana, sand at Waukegan; Au. 16, 28, S. 25. 



Promaehiis vertehratus Say. H.l, Au. 22. 111. A common robber-tiy. 



Asilus angustifrons Will. (Coquillett, det.). H.6, Je. 9. No 

 other Illinois record. 



Rhadiurgus leucopogon Will. (Coquillett, det.). H.2, 3; Au. 12, 

 17, 18. (8) This robber-fly is common at Devil's Hole. No 

 other Illinois records. 



Mesogramma politus Say. H.2, Au. 19. 111. 



Mesogrnmma margliiata Say. H.2, Au. 19. 111. 



Volucella fasciata Macq. H.l, 2, 3, 4; Je. 6, 8, 23, Au. 12, 13, 14, 

 17, 18, 19. (14) This odd little syrphid is one of the charac- 

 teristic blow-sand species. The larvi¥ breed in the tissues of 

 the cactus (Opuntia humlfusa) which grows abundantly in 

 this region (Smith, '91, Williston, '91). The adults are often 

 seen flying about, and abound on roadside flowers, such as 

 Verhena, dandelion, sweet clover, etc. No other Illinois 

 records. 



Conops sylvosus Will. H.3, Au. 14. No other Illinois record. 



Conops xnnthopareus Will. H.l, 2, 4; Je.6, 7, Au. 18. (4) 111. 



Zodion ohliquefasciatum Macq. (Icucostoma Will.). H.2, 6, Pekin ; 

 Au. 12, 18. (3) Urbana and Sandwich; July 25 and 28. 

 Carlinville (Rob. ). 



