Prof. Smith has been to London, and now radically changes the synonymy in the genus Acronycta, which I had hoped was to have been finaliy settled in the revision which was published by him and myself. The chanses involve the identification of three of Guenée's species and one of Walker's. As to impleta, Walk., we must accept Smith's identification as luteicoma, G. & R. I would suggest that the type ought now to be destroyed, lest future changes in the synonymy result. Guenée described eighteen species of Acronycta from North America, of which the larvæ of six were mentioned. In a genus like Acronycta, where the imagoes are so similar as not to be readily differentiated by description, while tire larvæ are very diverse, the larval descriptions are relatively important. Of the three species now changed (clarescens, Gn.; hamamelis, Gn.; brumosa, Gn.), two have original larval descriptions. As to clarescens I have no comment, especially as Grote's first identification is now restored. But the others are different. Hamamelis, formerly referred to an oak-feeding species (inclara, Smith), is now transferred to afficta, Grt. But Guenée's description contradicts afflicta in the colour of the hind wings, whereas it fits well the species named subochrea by Grote, better even than it fits inclara, and to this the larva also applies. As to brumosa, Smith says (Revision, p. 118) “the original description will fit either one of two or three species.” The characterization of the larva should then be allowed to prevail and the name be referred to inclara.