132 Journal New York Entomological Society, t^'o'- ^^^"^'f 



light yellowish beneath, not suffused with dusky except on the tarsi, mostly 

 sparsely black-haired but with a few pale hairs beneath toward the bases of 

 the legs. Abdomen pale brown, becoming more or less blackish terminally, 

 rather strongly and closely black-haired, the apical lateral tufts long, beneath 

 yellowish white, thinly short black-haired. Wings iridescent white, the costal 

 veins and basal part of the longitudinal veins brownish yellow, the costa con- 

 siderably thickened beyond the end of the first vein which joins the costa 

 much before the first crossvein, the costal border of the marginal cell from 

 one and one fifth to two times as long as the costal border of the first sub- 

 marginal cell, the first basal cell distinctly more than twice as long as the 

 second basal cell. Auxiliary vein incomplete. 



7. Olfersia wolcotti new species. 



Of the same size and general appearance as O. aniericana Leach, above 

 redescribed, but the front much narrower, not wider than the breadth of an 

 eye, the orbital margins subparallel or but slightly narrowing anteriad ; clypeus 

 only about one half as long as the front, the apical section somewhat narrower 

 basally but its apical emargination distinctly deeper and less broad, so that 

 the visible width along the dividing sulcation is nearly one half of the distance 

 between the lateral apices ; palpi blackish, twice as long as the clypeus ; gen- 

 eral coloration of head and thorax darker, dark reddish brown rather than 

 yellowish brown as in americana, the legs strongly suffused with blackish ; 

 wings faintly dusky, the costal veins and basal part of the longitudinal veins 

 blackish. 



Type. — Ann Arbor, Michigan, on a broad-winged hawk (Bntco 

 platypterus) shot in the woods west of the town, April 20, 1894, by 

 R. H. Wolcott (Coll. No. 129). 



Named in honor of Dr. R. H. Wolcott, in recognition of his valu- 

 able work both in entomology and in ornithology. The size of the 

 species precludes its confusion with any other except O. amcricana. 



For convenience in separating the above seven species of Olfersia 

 the following table is offered: 



Size larger, the length to end of wings 10 mm. or more; palpi longer than 

 clypeus. 

 Front narrowing anteriad, distinctly broader than an eye; coloration yel- 

 lowish americana. 



Front subparallel, not broader than an eye ; coloration dark brownish, 



wolcotti. 

 Size smaller, the length to end of wings not over 8 mm. 



Front subparallel, not broader than an eye ; palpi longer than clypeus, 



angustifrons. 

 Front distinctly broader than an eye; palpi subequal to or shorter than 

 clypeus. 



