AMERICAN DIPTERA. 27 



I have but a single eastern specimen of this species, in which the 

 tibiae have no yellow pile. 



49. Dasyllis astur 0. Sacken, West. Dipt. 285. 



I have twenty specimens from California, Washington Territory and 

 Oregon. They vary much and the species is doubtfully distinct from 

 the foregoing : four specimens have the legs wholly black pilose, and with 

 exception of the pile of the front being in part or wholly yellow, are 

 typical posticatae in appearance. All the rest have, however, tuore or 

 less yellow pile on the front legs and coxae, and sometimes a lesser quan- 

 tity on the middle tibiae. The yellow pile near the tip of the abdomen 

 varies in extent; it usually extends over three segments; in some, how- 

 ever, only on one. As Baron Osten Sacken remarks, I find the pile of 

 the head and pleurae variable. Two male and female specimens from 

 Western Kansas have the four front legs thickly yellow pilose, and the 

 yellow on the abdomen extending on the sides quite to the base. 



50. Dasyllis coluiiibica "Walker, Osten Sacken, West. Dipt. 285. 



Eight specimens from Oregon and Washington Territory I recognize 

 as this. The species is more slender, and less thickly pilose than the 

 preceding, especially on the thorax where the pile is shorter. Across the 

 dorsum it is more or less black ; on the posterior part longer, thicker and 

 sometimes orange colored, or reddish. The hind tibiae as well as the 

 front and middle pairs have yellow pile. 



HYPERECHIA. 



Schiner, Verh. Zool. Bot. Ges. 16, 67."5 (186t)). 



A single specimen from Pennsylvania, that has been in my collection 

 for several years, I have not been able to identify with any described 

 species. In size and appearance it resembles Dast/Uis fergissa, but offers^ 

 very distinct generic differences. From a study of Schiner's definition of 

 Hyperechia^ and also of the type species, Laphria xylocopiformis Walk., 

 it seems probable that it belongs to that genus, and yet it may have differ- 

 ferences that Schiner does not mention ; I therefore give its structural 

 characters : 



Very large, robust, black; densely pilose. Head broader than in 

 Dasyllis, considerably broader than high. The inner borders of the eyes 

 nearly parallel. Face gibbose below, but even, convex from the 

 antennae to the mouth, the convexity being greater below, densely cov- 

 ered with long hair. Antennae short, slender, not as long as the face, 

 second joint only a little shorter than the first, cylindrical and more 

 slender ; third joint slender, a little broader at the base, scarcely longer 

 than the first two together, terminating in a small but very distinct 



