In the March number fo The Canadian Entomoloigst, Page 74, I described a, to me, unknown larva, which, according to a statement of Mr. Wm. Beutenmuller, of the American Museum of Natural Histroy of New york, is that of Datana robusta, Strecker. Heretofore the imagoes of D. robusta had all been taken in Texas, and Dr. Dyar in Prof. Packard's Bombycine Moths, Vol. 1., page 120, is quoted as saying that the larva of Robusta was yet unknown. Some have claimed that the species described as Robusta too much resembled Perspicua, but it will be seen that the larva is distinct, and the imagines of both these species are entitled to the names as first described. The body colour fo Robusta larva in black, and the lines are yellow.