222 Annals Entomological Society of America [Vol. VI, 



A pupa removed to a watch glass with the bottom covered 

 with moist filter paper executed the digging movements for a 

 day or more, but failed to emerge. One reared in a very small 

 amount of sand and between two glass plates dug to the surface 

 and then back into the sand again. It emerged in imperfect 

 condition within the sand. 



III. Other Species. 

 Work on the European species of the family Bombyliidae is 

 also far from extensive. Dufour gave an account of the larvae, 

 pupae, and adult habit of Bombylius major. He found this 

 species in March 1857 on the sloping banks of sand hills with 

 southern exposure. He saw the fly light quickly at the openings 

 of the burrows of IJymenoptera. In the locality, the burrowing 

 hymenoptera were principally Andrenidse and especially Colletes 

 hirta. Dufour was never able however to find the egg of the 

 fly. Williston '08, p. 213, summarizes the known hosts of the 

 Bombylidae. In connection with the study of Spogostylum 

 anale (July 30), Artthrox impiger was seen resting on the ground 

 touching the abdomen to the surface of the sand. Anthrax 

 impiger Coq. (July 16-30), lights on blossoms of horse mint, 

 etc. or rests on other objects on the ground. Two, a pair, of 

 Exoprosopa fascipennis Say were taken while flitting before a 

 burrow of Microbembex monodonta. 



IV. Ecological and Geographic Distribution. 

 1 . Ecological Distribution of Parasite and Host. 



Near Chicago, the fly larvae appear to be confined to C. 

 Lecontei. - One or two larvae of C. hirticollis which do not 

 occur with those of C. Lecontei were found to bear similar 

 parasites. Adults of Spogostylum have never been seen near 

 the C. hirticollis habitat. C. purpurea limbalis which lives 

 on steep clay bluffs is parasitized by a larvae somewhat different 

 from that of Spogostylum. 



In 1907 and 1912 I pointed out that the development of 

 vegetation upon the sand areas at the head of Lake Michigan 

 takes places in an orderly fashion. Cottonwoods are the pio- 

 neers and are accompanied by Cicindela lepida. Only one 

 Spogostylum anale Say has been seen in these localities and this 

 when a strong wind was blowing from a more favorable habitat. 

 The cottonwoods are succeeded by pines and Spogostylum is 

 rare among them. Cicindela formosa generosa occurs in the 



