April, 1907.] Robber Flies of the Genus Philonicus. 117 



are not so prominent as in some of the other species of the genus. 

 Wings hyaline ; legs largely reddish, coxae colored like the thorax, 

 femora with more or less black on the outer side, especially on 

 apical half; tibiae and metatarsi black at apex, other tarsal seg- 

 ments mostly black. Abdomen dull black, before the incisures 

 with narrow white bands, in the front margin of which there 

 are on either side in each two or more bristles. 



Length, 17 millimeters. Male and female taken in south- 

 w^estern Colorado, July Uth, LS99, by E. J. Oslar. 



Philonicus obscurus n. sp. General color dark w^ith the wings 

 pale fumose all over. The abdomen has different shades accord- 

 ing to the view taken. Gibbosity of the face small with a few 

 bristles, part of which are black and the others white; face with 

 gray pollen, front with some small black bristles and occiput 

 above with a row of black bristles; antenna black, first segment 

 longer than the second, third, exclusive of the arista, about as 

 long as the other two; arista a little shorter than the third seg- 

 ment. Thorax brownish gray pollinose, with a middorsal dark 

 brown stripe narrowly divided before, and on either side two 

 spots of the same color, one before the transverse suture and the 

 other behind it. Wings uniformly darkened all over, but it 

 would not be far wrong to say they are hyaline. Legs black and 

 reddish; coxae colored like the sides of the thorax, femora 

 entirely black except that the posterior ones are often narrowly 

 yellowish at the extreme base; tibiae reddish at the base and 

 black at the apex; the extent of these two colors on the tibiae 

 is somewhat variable, the tendency being for the black to be 

 most extensive on the outside and the reddish on the inside ; 

 feet w^ith the first two segments reddish on basal part, other 

 segments usually entirely black. Abdomen opaque black, 

 before the incisures with gray bands, in the front margin of each 

 of which on either side are two or inore distinct bristles. 



Length, 13-16 millimeters. A male from Kentucky, across 

 the river from Cincinnati, collected by Chas. Dury, two females 

 from Washington, D. C, and males and females from Riverton, 

 N. J. and Pendleton. N. C. procured from Prof. Chas. W. Johnson. 



Philonicus rufipennis n. sp. Gibbosity of the face small, fur- 

 nished with a few bristles which usually are all white, but in 

 one or two of the specimens studied there is now and then a black 

 bristle intermixed ; face and front with silvery pollen ; a row of 

 black bristles on the occiput above ; first segment of the antenna 

 black, second largely yellowish and shorter than the first, third 

 black, not quite as long as the first two together, arista slender, 

 about the length of the third segment; beard entirely white. 

 Thorax gray pollinose, with a middorsal brown stripe narrow^ly 

 divided before, and two spots of the same color on either side, 

 one before and the other behind the transverse suture; coxae 



