† [This name having been previously used by Mr. Butler, for a genus of the Sphingidæ, it has been withdrawn by its author, and Systasca substituted for it. See this journal, vol. ix., p. 120.—J. A. L.]

^* The frenulum of many authors. —L.]

^* The tibial epiphysis of Guenee and of Edwards' Catalogue.—L.]

^* [Hinterbreast:—Metasturnum (Burmeister), postpectus (Kirb).—L.]

^* [Generally known to American Entomologists as the submedian vein.—L.]

^* See this excellent work: “The Geographical Distribution of Animals, by A. R. Wallace; Authorized German edition by A. B. Meyer, 1876.” I would here call attention to the fact that the boundaries of the first primary region of Mr. Wallace, which he names Palæarctic, almost exactly coincide with those of our European region. The only diffetence is thaf Wallace places the boundary farther south—in Africa to the Tropic of Cancer, in Asia to the Himalaya range, and farther eastward into the south of China. But this difference can hardly be considered as such, for, Lepidopterologically, we cannot determine the southern limit of these almost unknown regions, but hypothetically. Moreover, Wallace's boundary lines do not rest upon a very sure basis; Japan and Northern and Central China are overlapping provinces of such mixed animal population that we are almost as well justified in adding them to the northern adjacent (Indian) Faunal-province as to the southern. Thus, then, nearly the same result has been reached in two different ways. Ours, which is only applicable to one order of insects, is based upon a plain comparison of the statistics of the local Faunas known to us, and the principle laid down by Schouw, according to which that part of the earth's surface which is to be established as a natural kingdom rnust possess at least one-half of its species and one-fourth of its genera as peculiar to itself. Wallace, in his investigations embracing the whole domain of zoology, lays the principal stress on the distribution of the Mammalia, and takes into consideration their present and also their pre-historic condition, as far as the latter may be deterrlined from the fossil remains in former epochs of the earth. Now, if two divisions of the animal kingdom, so widely distinct, both by their organization and means of distribution, as the mammals and butterflies, return essentially the same answer to the zoographer respecting the extent of the region to which our division of the world belongs, this, certainly, may be considered a strong guarantee of the probability that we have made no mistake, but that we have, indeed, found a region which is consistently natural in all its belongings. For the present I retain the old name of European Faunal-region, together with its accustomed boundaries, which will be in conformity with Staudinger's Catalogue. Staudinger, as is well known, annexes thereto Arctic America, and for good reasons, although on no better grounds than our Transatlantic colleagues would have in adding to their Faunal-region the Arctic portion of the Eastern hemisphere.