Mr. Edwards describes and figures a female of this large species, from Michigan, in Proc. Ent. Soc., Phil. 1863. The following is a description of the male, collected by me in Iowa, July 4. The spots are numbered as in Mr. Edwards account:

The secondaries, above and beneath, are like those of the female.—Above. from the border of the primaries to near the base, the color is yellow, except the sexual dash and dark veining; an oblique line at end of the cell, from which a dark shade extends to the outermost spot; resting midway on this, a narrow shade runs from the first three spots along the subcostal vein.