SARCOPHAGA AND ALLIES 199 



Front .160 of head (average of five, — .145, .157, 

 .158, .164, .175) ; third segment of abdomen with an 

 incomplete row of marginal bristles; forceps evenly 

 curved forward to a sharp tip ; anterior claspers with 

 an elongated lobe underneath the apex; the distal 

 segment of the penis is rather small, produced into 

 a slender process which curves forward, bearing on 

 the front side two pairs of slender processes, longer 

 than the preceding, and a long curved fringe which 

 extends forward in a slender prolongation supported 

 by a darker colored thickening. Middle tibia with 

 dense villosity and with two bristles on outer side. 

 Hind femora curved slightly, stouter than in thatunu. 

 The villosity of the hind tibia long and dense, spread- 

 ing both ways. 



Female. Front .295 of head. One pair well 

 developed ant acr; no apical bristles on scutellum. 

 The pollen on the abdomen consists princij^ally of 

 four spots on the anterior part of each segment, the 

 posterior half of the segment being almost entn-ely 

 shining black. The males show this peculiarity in 

 a more or less degree and in thatuna it is still less. 

 The fourth segment of abdomen broadly yellow at 

 apex; genital segment yellow, retracted, forming a 

 vertical slit, fringed with a scattering row of long 

 black bristles. Wings rather distinctly infuscated, 

 especially near the base. 



Length 6 to 14 mm. 



Five males and one female. The holotj^pe is 

 from Moore's Lake, Idaho, collected July 10, 1907, 

 at an altitude of 6300 feet. It is the largest speci- 

 men. One male Moscow Mountain, June 1, 1907; 

 one male Vancouver, B. C, July 25, 1907, collected 

 bj^ R. V. Harvey (Prof. Hine's collection) ; two 

 males and one female Friday Harbor, Wash., May 

 29 and June 1, 1906. All collected by the writer ex- 

 cept as indicated. The specimens vary so much in 

 size that it is difficult to believe that they all come 

 within one species. However, no differences have 



