obstacle has been produced from the little attention paid to exotic {iv}Lepidoptera by modern Entomologists. More than two-thirds of these Illustrations are illustrative of that beautiful order of insects; and yet, with the exception of some of the showy butterflies and moths, scarcely a reference is to be found even in the works of Fabricius, the personal friend of Drury, whose Entomologia Systematica, published in 1793 and 1794, contains the last general summary of the species of this order; Gmelin also, whose Systema Naturæ it has been the fashion to decry, but which, as a laborious compilation from the works of preceding and chiefly Continental authors, is of great service,[2] was only acquainted with these illustrations through the early works of Fabricius.[3] It is true that M. M. Boisduval and Guérin have respectively published various new exotic Lepidoptera, especially of the Nocturnal group, in the Voyages of the Coquille and Astrolabe; but we still want a general revision, not only of the species but of the genera of this order. It was to have been hoped that, as regarded the Javanese species, this would have been effected by Dr. Horsfield, whose work upon the Lepidoptera of Java, as far as published, leaves nothing to be desired of the structural details of the species illustrated therein. M. Boisduval also, in his Histoire Naturelle des Lépidoptères, has treated the subject in a masterly manner, availing himself both of the preparatory states and veining of the wings; but we greatly miss those beautiful details which render the works of Horsfield and Curtis invaluable. It is in this comparative ignorance, both of the structural and metamorphotic details of exotic Lepidoptera, that we may attribute the want of a sound and philosophical distribution of the order in question; and which at the same time prevents us from determining the situation of many remarkable and anomalous groups. Of these the genera Castnia, Urania, &c. and the whole tribe of the Zygænidæ may especially be mentioned; and it is with the view of inciting enquiry into this part of the subject, that I have introduced many of the latter species into the genus Callimorpha amongst the Nocturnal moths. Another obstacle has been produced by the little attention paid by the Entomologists of the last century to the geographical situation of their insects; as an instance of this, it will be sufficient to mention that Linnæus and Fabricius made use of the term "In Indiis" generally, to indicate that an insect was an inhabitant either of the West or East Indies. Drury indeed appears to have paid more than the ordinary degree of attention to this part of the subject, as appears from the Catalogue of his Insects, which I obtained at the sale of Mr. Donovan's collections, to whom, as appears by a note, they were presented by Mr. Drury. Thus under Lucanus interruptus, (Genus Passalus, Fabricius,) we find the {v}following entries:--