Since the original illustration and description of this species, ten years ago, in the Proceedings of the E ntomological Society of Philadelphia, it has not been noticed, except by the late Mr. B. D. Walsh, in the same Proceedings, vol. 5, p. 194-5. I have been since last year indebted to Prof. C. V. Riley for a number of specimens of perspicua, raised from larvæ found on Sumach. It is enough to say that the specimens bear out the specific validity of a form which is perhaps the most easily recognized among the difficult species of this genus.