In his earlier works, _Mantissa_ and _Species_, Fabricius made no important change on the Linnæan method; but the many additional species which had come to his knowledge when he drew up his _Systema glossatarum_, led him to establish many new genera, and remodel the arrangement of the old ones. This method consists of forty-one genera, most of which have been adopted by subsequent authors; but it is less complete than it might otherwise have been rendered, owing to the death of the author before it was finished. Latreille did not deviate materially from the Fabrician method, adopting nearly all the genera; but he did not derive the distinctive characters exclusively from the antennæ and palpi, as the Danish entomologist had done, but had recourse to other parts of structure, and likewise judiciously took into account the peculiarities of the caterpillar and chrysalis. Several arrangements were proposed subsequent to or contemporaneous with that of Latreille, such as those of Lamarck, Dumeril, Dalman, &c. but most of them are of little importance. The last mentioned individual, however, appears to have been the first to apply to actual practice, in his description of the lepidoptera of Sweden, characters derived from the neuration of the wings, the value of which were first pointed out by Mr. Jones, in a paper in the Linnæan Transactions, published in 1794. Godart, without appearing to have been acquainted with what had been done by Dalman, likewise had recourse to the structure of the wings in his arrangement, as published in the Encyclopédie Methodique, and Lepidoptera of France. In the latter work, the diurnal series is classified with reference to the appearance of the discoidal cell in the inferior wings; and by adopting this excellent character, he has, in most instances, greatly improved on Latreille’s method. In 1776, an arrangement was proposed which attracted little attention at the time, but which has since risen to considerable distinction. It is that exhibited in the Systematic Catalogue of the Lepidoptera found in the neighbourhood of Vienna, by MM. Denis and Schiffermüller. This original and highly valuable system is entirely founded on the appearance of the caterpillars. It is singular that characters almost exclusively drawn from that state, should confirm the classifications founded on characters afforded by the imago or complete insect. But to such a degree does this coincidence obtain, that almost all the families proposed by the Austrian naturalists have been adopted as genera by those who were guided by other principles. This method remained for a long time almost unknown to the naturalists of this country, and even on the continent its excellence seems to have been but inadequately appreciated, except among the Germans. The only authors that have acted upon it are Ochsenheimer, and his continuator Treitschke, in their valuable and extensive work on the Lepidoptera of Europe[26].