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 undervalue, the labours of those who were engaged in the same field of inquiry.

About the period of Adanson’s return to Europe, which took place in 1754, natural history had undergone a very important revolution, from the valuable, though widely differing, labours of Buffon and Linnæus. The one, giving loose to his imagination, pursued a path as seductive as beautiful; the other, entering with minute discrimination into every department, furnished a text-book to philosophers; leaving the splendid paintings of his eloquent rival to those who delight rather in brilliancy of colouring, than in the chaste portraiture of nature. Both of these distinguished men, from too closely confining themselves to their individual views, appear to have, in a great measure, overlooked a most interesting branch of their subject, viz. the general relations of all beings, from which is deduced the division of them into families; which division is founded on their peculiar characters. This had formed an important branch of Adauson’s solitary reflections, and the boldness with which he developed his views soon attracted the admiration of naturalists. To appreciate thoroughly the value of his labours, it will be necessary to exhibit a rapid sketch of the general principles which influence natural arrangements, and the particular views entertained by Adanson.

Every organized being is to be considered as an assemblage of parts, which, by reciprocal actions, produce certain effects. Between all of these parts a mutual dependence subsists, and no modification can be effected in any one member of the series without sensibly affecting all the others in a greater or less degree. It is obvious, that there can only be a certain number of possible combinations; which may be divided into two great classes, the primary and the subordinate.

The first step towards the knowledge of these combinations would be an accurate acquaintance with all the actually existing organs. If this were attained, and if a complete view of all possible combinations were deduced, every organized being would be allotted to a determinate place, according to its organs; and there would be a correct systematic arrangement of all organic nature; every relation, every property, would he reducible to general laws; every function might be demonstrated; and natural history would become a precise science. Such, however, is only the ideal perfection at which we aim in attempting natural methods, to which we cannot expect the rapid advance fancied by some visionary theorists, but to which a steady perseverance, unclouded by preconceived prejudices, will ultimately enable us to approach.

The most direct means of calculating the effects of the before-mentioned modifications would be to determine the function and the influence of each organ. In this way, the great divisions might be made according to the most important organs, and the inferior would be naturally founded on the relations of the less important organs. A scale would thus be established, not less correct as regarding the order of nature, than if it had been formed subsequently te a full examination of all her works. This principle of classification has been named by some philosophers “the subordination of characters.” It is rational and philosophical; but its application presupposes an advancement in science far beyond that which existed at the period when Adanson commenced his labours. Accordingly, he adopted a more experimental methed—that of a complete comparison of species; and the mode of applying his scheme is abundantly ingenious, and entirely his own.

He founded his classification of all known organized beings on the consideration of each individual organ. As each organ gave birth to new relations, se he established a corresponding number of arbitrary arrangements. Those beings possessing the greatest number of similar organs were referred to one great division, and the relationship was considered more remote in proportion to the dissimilarity of organs.

The chief defect of this method consists in presupposing a knowledge, not less difficult of attainment than the former,—of species and their organization. It gives, however, distinct ideas of the degree of affinity subsisting between organized beings, independent of all physiological science. Of this “universal method,” as he called it, Adanson gave some account in an essay contained in his Treatise on Shells, published at the end of his “Voyage au Senegal.”

Until the appearance of this work, the animals inhabiting shells had been much neglected. On this branch of his subject, our author exercised his wonted zeal, while his methodical distribution, founded on not less than twenty of the partial classifications already alluded to, is decidedly superior to that of any of his predecessors. Like every first attempt, however, it had its imperfections, and these arose from not having examined the anatomical structure of the animals; from which cause he omitted, in his arrangement of the class of Mollusca, all molluscous animals without shells.

His original plan was to have published the whole of the observations made during his residence at Senegal, in eight volumes; but being deterred by the difficulties attending so extensive a publication, he abandoned the scheme, and applied himself entirely to his “Families of Plants,” which he published in 1763. In this he found the application of his general principle not less advantageous than in his preceding works.

The distribution of plants into natural families has attracted the notice of botanists since the middle of the seventeenth century. Bernard de Jussieu, the friend and instructor of Adanson, bestowed much attention on this subject; but, dissatisfied with his success, has left no other memorial of his labours than the arrangement which he introduced in the gardens of Trianon in 1758. Prompted by his own bold genius, as well as by the example of so distinguished a friend, Adanson undertook the task; and although he fell into errors which had been avoided by Jussieu, he executed it, upon the whole, with consummate ability. In the preface to this work, he gave an elaborate account of the history of botany; and here it is not difficult to perceive that one of his chief objects was to insinuate his own claims to be placed at the head of scientific botanists.

In 1774, (eleven years after the appearance of his Families of Plants,) he submitted to the consideration of the Academy of Sciences an immense work,