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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.
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, (Floræ 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 (Dipsaceæ Jus:,) 8 Tricoccæ (Euphorbiaceæ Jus:,) 12 Labiatæ, 13 Siliquosæ, (Cruciferæ Jus :.) 14 Columniferæ, (Malvaceæ Jus :)) 15 Leguminosæ. 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 wbicb 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
bryo, receptacle, &c. and on every peculiarity, however, unimportant or trifling'; and then, from these systems, he compounded his great scheme of natural families. His artificial systems were all bad, his natural arrangement no better. The former, however, may be considered as admirable studies, and if carried faithfully through the different genera, elucidating every particular organ which belongs to each, they would furnish a mass of information that every student of this science would desire to possess. But when he undertook to compose his natural families, from some error of judgment or perverseness of understanding, he was led to consider every feature, organ or function in a vegetable as of equal importance and value, and to conclude, therefore, that the plants in which the greatest num, ber of these features are found, must consequently be most nearly allied. Experiment proved this theory to be incorrect, and the natural families of Adanson are as incongruous as those of his predecessors,
It was at this time, and with so much preliminary knowledge, that Jussieu commenced his studies on natural orders, and tested his principles experimentally, by arranging, according to his views, the plants in the garden of Trianon, then under his direction. He differed from Adanson totally, and as time has proved, correctly in his fundamental doctrines. Considering the seed as the great and final aim of the vegetable, as the last term of one and the salient point of another generation, he sought in that organ the essential principles of the life and form and structure, and duration of the plant. In the cotyledons, in the perisperm, in the position of the embryo, in the direction of the plumula and radicle, he found qualities more unchangeable than in any other part of the vegetable. The modifications of these parts of the seed formed the leading characters of his classes. When he was obliged to obtain aid from other portions of the fructification, he considered the position of the stamens whether superior, inferior, or surrounding the germ as more important and invariable than the number. By the combination of these principles, he was enabled to distribute all plants into a few leading divisions or classes. Subordinate characters, the number of stamens, the presence or absence of the calyx or corolla, their form, their position, aided in breaking these classes into smaller sections and in forming orders, containing no genera but those very intimately allied.
Bernard Jussieu, from great diffidence, as his friends relate, never published any of his views on botany, any exposition or vindication of his opinions. He explained them to his pupils, and exhibited them publicly in the gardens he superintended, and they might have been given to the world under other names, if a nephew of similar tastes and equal talents had not undertaken the task of presenting to the public a view of this system, and an elaborate illustration of the principles on which it is founded. It was about 1759,' that this arrangement was first made known in Paris ; in 1789, that the “Genera Plantarum secundum ordines naturales disposita," was published by Anthony Laurence de Jussieu.* And in the forty succeeding years, through which the life of this illustrious botanist has been extended, he has been devoting his talents to the perfect developement of its doctrinés, enlarging, improving, modifying them by the aid of all that knowledge which his own labours, and the researches, and the criticisms of the many distinguished men whom the last half century has produced, have been diffusing over this science.
When the sexual system of Linnæus was first announced, its clearness, its precision, its applicability, gave it an immediate and almost universal acceptance. A few old botanists who had been educated in the school of Tournefort, and a few who had proposed, and consequently wished to establish systems of their own, alone opposed its adoption. Wherever it was tried, it gained immediate fayour. The arrangement of Jussieu on the contrary, has crept slowly into use, and had it not been sustained by something like national pride, and explained, illustrated and defended by the great number of eminent botanists, who have flourished in France since its appearance, it might have been laid aside as an ingenious but impracticable theory. It will not be irrelevant to our present purposes to consider the causes which obstructed its popularity.
In the first place, it must be admitted that for all practical purposes, the ground appeared to be completely pre-occupied. When the system of Linnæus was published, the want of some good scheme of arrangement was universally perceived. Those who used the system of Tournefort, felt its difficulties and defects, even after it had been beautifully re-modelled by De Bergen, in 1750. But when the natural orders of Jussieu were proposed, the Linnæan system had entire possession of public opinion, it seemed to supply every wish, excepting that which the author had himself suggested of an undefined and seemingly unattainable natural arrangement. And as a practical method, one, at least by which the appropriate place of any plant can be easily discovered, and consequently the fact of its
* The method of Jussieu was adopted in 1774 in the Jardin du Roi," and the principles of the system explained in a memoir presented to the Academie des Sciences, by A. L. de Jussieu, in the same year.