1911] Promachus and Proctacanihus 160 



This species may be separated from albifacies by the gray 

 instead of brown pollinosity of the thorax, and sides and venter 

 of the abdomen, by the wings being more nearly hyaline and 

 by the gray shadow in the first submarginal cell being narrower 

 and less sharply defined than in that species. 



The species is known from California, Oregon and Wash- 

 ington. 



Promachus bastardii Macquart. 



Asilus laevinus, Trupinea rubiginis and Asilus ultimus of 

 Walker, and Promachus philadelphicus Schiner are considered 

 synonyms. 



Total length 21 to 28 millimeters. Mystax and beard yellow, the 

 latter paler than the former, palpi clothed with black hair, oceipito- 

 orbital bristles black; thorax brown, the usual markings present on the 

 dorsum but not very plainly shown, legs in general color red with white 

 hair and black bristles; in most specimens there is a black stripe of 

 greater or less width on the anterior side of each femur, and the front 

 legs especially may have more or less yellow pile on the tibiae and 

 tarsi; wings quite distinctly uniformly brownish, shadow in the first 

 submarginal cell about half as wide as the cell at the widest part, not 

 very dark gray but with definite limits. Abdomen distinctly brown 

 on the venter and sides and clear black above. From dorsal view the 

 abdomen shows a very narrow band of white hair on the posterior 

 margin of each segment and black hairs on a clear black background 

 otherwise. 



The hypopygium is clothed with silvery white hair above 

 but is distinctly wider than in albifacies and princeps. 



Specimens have been taken in New York, Massachusetts, 

 Pennsylvania, Michigan, Kansas, Georgia and Ohio. 



Promachus quadratus Wiedemann. 



Total length 22 to 29 millimeters. Mystax and beard yellow, the 

 latter distinctly lighter than the former, palpi black with yellow hair, 

 but with a few black ones intermixed, rear of the head with yellowish 

 hair, occipito-orbital bristles black. Thorax light brown pollinose with 

 the usual middorsal stripe and lateral markings; wings very pale yel- 

 lowish all over, shadow in the first submarginal cell narrow, hardly 

 one-fourth as wide as the cell at the widest place ; legs brown with light 

 hair and black bristles, anterior part of each femur darker than the 

 other parts of the leg; balancers brown. From above each abdominal 

 segment has a rather -wide posterior margin which is clothed with pale 

 yellowish or white hair and which widens distinctly towards each side. 

 The ground color of the abdomen is black and the color shows plainly 

 on the anterior part of each segment but not so extensively as in bas- 

 tardii. In the male the genitalia is of medium size and clothed above 

 with silver white hair as in related species. 



