In reply to Mr. Charles A. Hart, who has shown, in the last number of this journal, that in his opinion I am in error regarding the identification of Astatus bicolor, Say, I would say that the stigma of the ♂ only is “yellowish-rufous”, while that of the ♀ varies from reddish-black to deep black. If he will again consult my synopsis of the genus Astatus he will find that I used the words “stigma of wings black” in separating those of the female sex. In regard to my new species, A. pygidialis, which Mr. Hart suggests may be an exteme variety of bicolor, it differs not only in the slight characters mentioned by him, but also in the shorter and triangular pygidium, and the more feeble armature of the legs; the scutellum is not furrowed down the middle, and the insect itself is much smaller.