After continuing his physical studies with much ardour for several years, he at length appeared in the character of an author. His “French Flora, or a brief Description of all the Plants which grow naturally in France,” was published in 1778. The immediate occasion of this work was a desire to furnish his fellow-students with a system of arrangement which should lead with greater ease and certainty to the determination of plants than any then in use. For this purpose he adopted a modification of the binary or dichotomous method, the principle of which consists in arranging natural objects by their positive and negative characters, dividing and subdividing always by two, and allowing a choice only between two opposite characters. Although this plan is, of course, highly artificial, and ill calculated to throw light on the affinities and analogies of objects, yet it is much recommended by its extreme simplicity, which adapts it to the comprehension of those who have but little acquaintance with the technical and descriptive language of natural history. If judiciously applied, it affords an easy index to particular genera and species, and renders the subject at once accessible without any preparatory labour. Indeed, the principle on which it rests must to a certain extent be implied in every artificial system of arrangement. This work soon acquired a considerable degree of popularity, not only by its intrinsic value, but from the seasonable time of its appearance. The study of botany, which had hitherto been confined almost exclusively to the members of the medical profession, was now becoming a popular and even fashionable pursuit; a distinction which it owed chiefly to the writings and example of J. J. Rousseau. Every work, therefore, calculated to facilitate the study, was likely to meet with a favourable reception among those who would probably have been repelled by dry technical details and rigorous scientific precision. Its publication had an important influence on Lamarck’s fortune and prospects. It secured for him the friendship and patronage of M. de Buffon, who was then in the height of his popularity, and possessed of much influence, not only from his rank, character, and celebrity, but also from his authority with the government. Even its want of a very philosophical and precise system was probably one of the circumstances that recommended it to Buffon’s attention, as it was thereby assimilated to his own writings, from which every thing of that nature was expressly excluded. Through his influence, an edition of the work was printed at the royal press, and its author introduced to the favourable notice of many of the leading savans of the day. He had soon an opportunity of turning his popularity to some profitable account, for a place happening to become vacant in the botanical department of the Academy of Sciences, Lamarck was presented with the appointment, in preference to others of older standing and much higher pretensions. He