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favourite principle on which schemes of classification were constructed. Many ingenious theories were built upon it, and if nature had been equally careful of this organ, in all plants, it world, perhaps have long continued the leading object of attention in this science. Rivinus in Germany, and Tournefort in France, made it the basis of their arrangements, which were celebrated and popular in their respective countries. That of Tournefort was developed with so much talent, with so much botanical knowledge, with so many improvements in the detail and in the description of plants, accompanied with the first accurate determination of genera, that it appeared at one time likely to become the dominant system of Europe. But it wanted simplicity, the classes founded on this organ alone were not natural, it was not sufficiently comprehensive, and as new plants were made known the number multiplied of those which had no corolla, or could with difficulty be placed in any of its divisions. Thus, while it acquired for its author great celebrity, it did not satisfy the wants of practical men. Other distinguished botanists were labouring to form systems, at the same time, philosophical and perspicuous. Magnol appears in his writings to have understood perfectly the principles on which plants ought to be arranged, and pointed out with great apparent judgment the track that it was proper to pursue. Yet the system which he published at the same time, and to which these remarks were prefixed, is founded almost entirely on the corolla, and is very inferior either to that of Rivinus or Tournefort, and thirty years afterwards, at his death, as the result of his mature reflections, he left a second still worse, founded on the calyx. So true it is, that some who, with almost prophetic inspiration, anticipate the improvements that future years will bring forth, have themselves but an indistinct view of their own conceptions, they utter opinions to themselves dark, to a future generation clear and distinct, and which, until fulfilled, have all the vagueness and mystery that give to prophecy its deep interest and awful power.

While commenting on those systems, and those only we wish to notice, whose principles have exercised some influence on the science, that of Hermann, founded on the fruit, and perhaps the best of those proposed, not on the structure of the seed itself, but on their accidents and disposition, whether naked or clothed, whether in berries, legumes or capsules, &c. deserves to be noticed. Besides its intrinsic merit it serves to corroborate the remark we have already had occasion to make, that these proposed methods, though in some measure discordant, all tended to improve the knowledge of plants. Thus the arrangement of

Tournefort required a thorough examination of the corolla, that of Magnol of the calyx, that of Hermann, and afterwards of Siegesbeck of the seed vessels, if not of the seed itself. In this unsettled state, amid these and many other theories which we have not time to enumerate, was botany, and every other department of natural history, when in 1735, the Systema Naturæ was offered to the world. The outline which it has since taken so many labourers to fill up, and whose portions or fragments it has required so many volumes to contain, was published in eight folio sheets. It contained a tabular view or arrangement of every branch of natural history, excepting the mineral kingdom, and presented the germ of all the future labours of Linnæus. Independent of all other considerations, this sketch is now become a great bibliographical curiosity. From infancy, this great reformer and founder of natural science, had been devoted to its study. His occupations, his amusements, his toil, his relaxation, were all modifications of the same passion. At the age of twenty-three, he began to compose those works, which gave a new direction and character to natural history, and which five years later he began to publish. He examined and studied, as might be expected, the systems of the day, but a review, it is said of a treatise of Vaillant's on the sexes of plants, first led him to consider the importance of the stamens, and styles in the vegetable economy. He soon perceived the variety that exists in the arrangement and position of these organs; their connexion with the fruit, and their definite numbers. He discovered that they were more universal than the corolla, in some respects more permanent and more unchangeable, more easily distinguished than the peculiarities of the fruit, and applicable to a wider variety of cases; and more definite than any portion of the flower that had yet been employed in classification. He tried them as the basis of a new system, and every examination or inquiry seemed to justify the choice. Instead of requiring modification as new plants were brought to view, or the creation of a class of "anomali"* to comprehend those that could not be forced into his established divisions, every discovery served to illustrate the universality of the principles he had adopted, every day's experience to manifest the simplicity and facility of their practical application. A century is nearly gone by, and the same praises may be uttered with unabated confidence. All that has been discovered in this age of discovery has been arranged as readily in this system as if it had been

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Many of the older systems had such classes. Johnston, (1661.) Morison, (1699.) Ray, and even Tournefort himself.

previously known and considered. So clear and definite and easy did botany become under its guidance, that if the old hesitated for some years whether they should adopt its arrangements, a race of young botanists sprung almost self-taught into existence, and spreading themselves, in triumph, over every accessible portion of the globe, loaded with ever-multiplying trophies, the system and its author. Such are its merits; its defects are those we have mentioned when speaking of artificial systems; that being founded on a few features or organs, it does not call for so comprehensive and thorough a knowledge of the affinities and intimate structure of plants, as must be acquired in the study of natural orders; that it has directed the attention of its followers too exclusively, to a small portion only of those functions which constitute the perfect individual; that the fruit and seed in particular have been too much neglected in the Linnæan school; that by using but a few characters, it includes in its leading divisions, groups that are in no respect allied, only brought together by one or two common features, whilst on the other hand, it has broken and separated families most perfectly natural.

From 1735, Linnæus continued to publish his many writings on natural history, which from that time, perhaps, ought to date its pretensions to the dignity of a science. For although his elementary works are professedly applied to botany alone, yet the principles are equally applicable to every other department, and have improved them all. The "Fundamenta Botanica,” "Critica Botanica," and "Philosophia Botanica," (not published until 1751) contain aphorisms or discussions on the fundamental doctrines of this science, while in his "Flora Lapponica," "Hortus Cliffortianus," "Genera Plantarum," and others, subsequently published, he was successfully describing the plants which grew around him, and those which the enterprize of his pupils, and the liberal efforts of many wealthy lovers of botany were annually bringing to his view. At length he collected them all together, and in 1753 published, perhaps his greatest work the "Species Plantarum." In this, for the first time, appeared in a general system, that innovation which has proved so great a convenience, and which probably will never be relinquished in natural history, the use of trivial names. This novelty introduced first in his "Pan Suecicus," in 1749, was immediately adopted, and has since been universally followed. It had formerly been necessary when speaking or writing of plants, to annex to the generic name some of those characteristic qualities which distinguish each species, as the means of indicating the one it was wished to point out. What we now

term the specific character, in the old writers sometimes very long, was used as a portion of the name. It is said that the

short, terse, pointed and precise characters that Linnæus gave to his species, were at first designed to be used in this manner, and the change was not acceptable to all. But experience soon removed each objection, and in every vicissitude which the original arrangements of Linnæus will have to undergo, although many parts of his system will be modified, reformed, perhaps finally superseded, this will remain. He himself will be viewed as the great reformer and legislator in natural history, and most of the principles which he announced will be held in perpetual remembrance, as the lights which guided his successors in their improvements and facilitated all their labours.

About thirty years after the publication of the sexual system of Linnæus, Bernard de Jussieu, professor of botany at the Jardin du Roi, made known that method, which is now becoming prominent in Europe, and which if not exclusively used must hereafter be studied by all who wish to be considered as profoundly versed in this science. If its characters are less prominent, and more varied, than those of its great rival, they are more intimately connected with the structure of the plant, therefore more philosophically correct, and if possible, its extent and grasp is more comprehensive, because from its very principles, new orders can be established without impairing its symmetry for any new plants that cannot with propriety be placed in an old one. While the basis of the system of Tournefort was established on the corolla, of Linnæus on the stamens and styles, that of Jussieu was made to rest upon the seed itself. Let us look back for a moment and trace the progress of this principle. In 1682, Ray published in England his "Methodus Naturalis Plantarum," and four years afterwards his "Historia Generalis Plantarum." In these works his leading divisions, (if we except the ancient error or prejudice, which perplexed even the accurate mind of Tournefort, and was not really vanquished until the time of Linnæus, of separating trees and shrubs from herbaceous plants, and making a separate classification for each) were founded on the cotyledons of the seed. This principle, however, was not pursued, although some natural orders were as usual distinctly marked. Boerhaave so illustrious in medicine, wished to distinguish himself as an eclectic in botany, and adopted parts of the systems of Ray, Herman and Tournefort, but he did not intimately combine them, which he might have done with sinVOL. IV.-No. 8. 62

gular beauty of effect; he only mixed them all and improved none. His primary divisions, however, were derived from the cotyledons of the seed. Van Royen, in 1740, (Flɔræ Leidensis Prodromus) used the same characters with far greater skill, and made great advances in the formation of what would now be called a natural system. Indeed, we doubt whether his merit has in later days been duly appreciated. It will be sufficient here to mention a few of his classes, to show what progress he had made towards the establishment of natural families. Monocotyledones-1 Palmæ, 2 Liliaceæ, 3 Gramineæ; Polycotyledones-4 Amentaceæ, 5 Umbelliferæ, 6 Compositæ, 7 Aggregatæ (Dipsacea Jus:,) 8 Tricocca (Euphorbiaceæ Jus:,) 12 Labiatæ, 13 Siliquosæ, (Cruciferæ Jus :.) 14 Columniferæ, (Malvaceæ Jus :,) 15 Leguminosa. These are all admirable divisions; even if some of them have been since subdivided, they possessed strong natural affinities.

It may be proper here to remark, that the distinction between natural and artificial systems, which has so much occupied the attention of botanists in modern times, owes its origin to Linnæus himself. It was his discriminating mind which first pointed out the distinction between a system which founded on all the analogies of nature, must comprehend in each of its divisions, only those objects whose affinities are on all points strong, and one which selecting only one or two prominent features, may place together forms in all other respects very dissimilar. It is known that Linnæus devoted much of his attention to the formation of a natural system in botany, and was not successful, the orders which he constructed and proposed to establish, have been handed down to us by some of his pupils, (Giseke and Fabricius) but the principles upon which he formed them, have not been clearly developed. Indeed, it is probable, that he himself did not distinctly see them, but was feeling his way, throwing plants as he studied them into groups, guided by symmetry and general analogies, expecting that he should in time be able to detect and point out the secret characters that connected and enchained them together. His remarks, however, made great impression. Adanson, one of the most ardent, devoted and indefatigable naturalists, that the world has yet seen, professing an utter contempt for artificial systems, and as if to shew the facility with which they could be created, if not their worthlessness, drew up sixty-five, each founded on some particular feature or function of vegetables-on their height, size and duration, on their juices, flavour, smell, on their roots, buds, leaves, stipules, spines, on their calyx, corolla, anthers, pollen, styles, stigmas, seed vessels, seed, em

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