150 Annals Entomological Society of America [Vol. XII, 



Erax pilosus n. sp. 



Male. Total length 1 1 millimeters. Hair and bristles of the whole 

 body white, except about four black bristles above the base of each wing, 

 numerous white bristles on the margin of the scutellum; wings delicate 

 hyaline, narrow, the third vein branches near the middle of the distance 

 between the anterior cross vein and the apex of the discal cell, stump 

 on the anterior branch much shorter than the basal section. Femora 

 all black, remainder of legs red with extreme apexes of tibise darkened. 

 Abdomen, except the first segment and anterior part of the second, with 

 abundant silver-white hair parted at the middle and directed outward. 

 Hypopygium from dorsal view of uniform width for almost basal half, 

 then gradually widened and rounded at tip; from side view nearly 

 uniformly convex dorsally and concave ventrally. See Figure 15. 



Male type from El Paso, Texas, April 5, 1902. Collection 

 Academy of Natural Sciences, Philadelphia. 



The small size, delicate appearance, male genitalia and 

 furry abdomen are characteristic of the species. I know of no 

 Erax where the long white hair of the male abdomen extends 

 to the tip of the seventh segment as in this one. 



Erax californicus Schaeffer. 



Male. Total length 24 millimeters. Vestiture of the head white, 

 with the exception of the ocellar and occipito-orbital bristles which are 

 black; mesothorax largely white hairy, but some black bristles near 

 the wing bases and some short black hair on the anterior part of the 

 dorsum. Legs long white hairy and with black bristles, femora black, 

 tibise and tarsi largely red; wings hyaline, furcation of the third vein 

 very near the middle of the distance between the small cross vein and 

 the base of the second posterior cell, stump slightly longer than the 

 basal section. Abdomen black, largely covered with white pollen and 

 everywhere with white hair, longer on two, three and four and directed 

 outward. Hypopygium from the side of nearly uniform width, rather 

 obliquely tinincate at apex, with a rounded prominence above and a 

 tuft of white hair pointing backward below. See Figure G. 



A female from the same locality is colored like the male. Oviduct 

 fully as long as the last three abdominal segments. 



The most characteristic thing about the species is the 

 absence in the male of distinct silvery abdominal segments, 

 contrasting with others that are not silvery. The whole 

 abdomen is white pollinose, but in no place is this so dense 

 that it may be said to be silvery as in most species. 



More than 20 specimens of both sexes ranging from Washing- 

 ton and Montana to California and Nevada, vary in size from 

 18 to 26 millimeters and show quite an amount of variation 

 in the color of the tibias and tarsi. 



