2 UniTcrsity of MicJiigan 



occurring in North Carolina and Massachusetts. It has been 

 collected in several states since and the records show that it 

 is partial to bare, sandy areas such as are present along lakes, 

 seas, and rivers and in semi-arid regions. I have collected 

 numerous specimens at Cedar Point, Sandusky, Ohio, on the 

 sandy shores of Lake Erie, and have observed it issuing from 

 the pupa-case which was left partially protruding from the 

 sand. Its larva, no doubt, is predaceous on subterranean ani- 

 mal life of its chosen habitat. Nearly a score of specimens 

 were taken along the shore of Lake Michigan, in Berrien 

 County, which is the first record of its occurrence in Michigan 

 known to me. 



Pupa. Three cast pupa skins of Proniachns riifus were 

 received with the adults. The pupae of different species of 

 Asilidae are much alike except they vary strikingly in size, 

 as is to be expected. The division into head, thorax, and 

 abdomen is plainly apparent and the segmentation is clearly 

 evident. The middle of each abdominal segment is expanded 

 into a ridge which entirely encircles its segment and bears a 

 row of spines which are stoutest dorsally. These rows of 

 spines dorsally near the middle of the length of the abdomen 

 are composed of slender, hair-like spines and short, heavy, 

 two-pointed spines alternating with one another. The location 

 of the eyes is easy to see. Just beneath each eye is a very 

 prominent complex spine with three long points, and between 

 these, but somewhat higher up, are two prominent spines with 

 enlarged bases, while behind each eye, near the middle of the 

 thorax, are two less prominent spines. Immediately behind 

 each eye is a thoracic spiracle. Total length 28 to 32 milli- 

 meters. This pupa differs from those of Asilus sericeiis and 

 Brax interruptus in not having distinct spines protruding from 

 its posterior end. 



