In regard to these Memoires, he remarks, that although he has endeavoured to give them some degree of connexion, they might for the most part be considered as independent of each other; and that his object was not to present a systematic description of insects, but to furnish materials for the use of future naturalists. It is therefore improper to say, that he wrote his work with an entire contempt of method; and certainly the notices which he collected must have required more time and talent than the mere arrangement of insects according to characters derived from their external form. "The number of observations necessary for a tolerably complete history of so many minute animals," he says, "is prodigious. When one reflects on all that an accomplished botanist ought to know, it is enough to frighten him. His memory is loaded with the names of twelve or thirteen thousand plants, and he is expected to be able to recall on occasion the image of any one of them. There is perhaps none of these plants that has not insects peculiar to itself; and some trees, such as the oak, give sustenance to several hundreds of different species. And, after all, how many are there that do not live on plants! How many species that devour others! How many that live at the expense of larger animals, on which they feed continually! How many species are there, some of which pass the greater part of their time in water, while others pass it entirely there! The immensity of Nature's works is nowhere more apparent than in the prodigious multiplicity of these species of little animals." He then proceeds to remark, that, as it is impossible for one man to acquire a knowledge of all the insects of even a limited district, and as thousands of minute insects must for ever remain unknown to us, instead of burdening our memory with the characteristic distinctions of these creatures, and thus preventing ourselves from attending to matters of more importance, it would be sufficient for us to know the principal genera, and especially those that are of most frequent occurrence, and to make ourselves acquainted with their peculiarities, their food, their propagation, the different forms which they assume in the course of their life, and such like circumstances. He avows that he had no great regard for a precise enumeration of the species of each genus; holding it enough to distinguish the more remarkable.