There have been described thus far three species of this genus from the United States, two of them known only in the male sex, the third known only in the female sex. A fourth species, known only in the female sex, is described below. The types of œqualis, Nort., and simplocicornis, Cress., are in the collections of the American Entomological Society, and I am indebted to Mr. J. Chester Bradley for examining these types and furnishing me with the notes on which the descriptions given below are based.