Mr. J. B. Lembert has kindly sent me some alcoholic larvæ of A. mariposa, and I may record a few points in comparison with the eastern A. octomaculata. Mr. Lembert has given the life history quite fully in the December number of the Canadian Entomologist, but our species have not been compared. The larva is especiaily interesting, as being the second one discovered in this genus. We have long been familiar with that of A. octomaculata, and everybody has described it; but the other species, though somewhat numerous, have remained unknown.