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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 coinpose 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 number of these features are found, must consequently be most near
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 thein 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 doctrines, 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 favour. 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 wbich the appropriate place of any plant can be easily discovered, and consequently the fact of its having or not having been heretofore described, can be readily and accurately ascertained, it is not to this day, and perhaps never will be surpassed. It would not, therefore, be readily abandoned, for one requiring more minute and comprehensive and accurate research ; to beginners more obscure and difficult, and consequently uncertain, even if the arrangements of the latter are more philosophical, and the knowledge obtained finally more complete. It appears to us, not improbable, that for a long time to come, a practical acquaintance with plants, will first be acquired through the few and simple elements of the Linnæan system, and then each plant will be arranged and studied more profoundly in connexion with those other species to which it is naturally allied.
* 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.
In the second place, there were, if we may be permitted to say so, some defects in the system, perhaps, we should rather say, in its exposition, which strengthened the objections made to it as one for common use. Bernard Jussieu first distributed all plants into seven classes. The Acotyledones, having no stamens; the Monocotyledones and Dicotyledones, each into three classes, with stamens hypogynous, perigynous or epigynous. A. L. Jussieu, to lessen the accumulation of orders in these classes, made use principally of the corolla, whether present or absent, whether monopetalous or polypetalous, to subdivide the Dicotyledonous plants into ten classes, and formed an eleventh of the plants, in which the sterile and fertile florets are essentially distinct, as in the Euphorbiaceæ, Amentaceæ, Coniferæ, &c.; these, with the four other classes, formed fifteen in the whole. Still, however, this, if it has lessened the inconvenience, has not removed the objection. The orders in each class have now no .natural connexion, they are held together by artificial ligaments, by the position of the stamens and the structure of the corolla, by characters which are considered by the author himself, as of secondary value. Hence, all who have attempted to modify this system, have only endeavoured, and as yet unsuccessfully, to arrange the orders in a natural and symmetrical series, and to establish other classes or leading divisions of the orders. But the more profoundly we study the arrangements of nature, the more sensibly we perceive, as remarked long since by Linnæus, that the vegetable as every other kingdom of nature, resembles a map rather than a chain, that it is composed of groups of kindred genera, surrounded on every side with occasional intervals by other groups, each connected on different points to distinct and distant families, while, perhaps, a single isolated genus interposes and serves on some of these points, as the connecting link. Whenever we attempt to arrange the orders, we find that there is no
successive series, that in truth, the vegetable kingdom forms a system of orders, not of classes.
In the third place, it may, perhaps, be said with truth, that the difficulties of this system were at first increased by the caution, if not timidity, with which it was developed. Its own principles were not carried to their full and legitimate results. Bernard Jussieu did not establish a great many orders, and A. L. Jussieu, with something like a fondness for even numbers, increased these orders in his “Genera Plantarum," in 1789, exactly to one hundred. In consequence, however, of this limitation, the orders of Jussieu contained many discordant materials, some of them were really not as strictly natural as some of the classes of Linnæus. There appeared at first a great unwillingness to take a single genus, a single plant, perhaps, as the type of an order; an apprehension that the system might be injured, at least as a practical one, by too great a multiplication of families. Yet on this point there can and ought to be no hesitation. If nature has chosen not to limit her models or types, our systems cannot restrict them; and if a thousand orders shall be necessary to exhibit or contain all the types which the vegetable kingdom unfolds, to a thousand orders, every system which professes to be founded on those types, must be carried. In this respect, the arrangement of Jussieu has already undergone some beneficial changes. In the last tables we have seen, the nuinber has been increased to one hundred and sixty-four; and this modification and, as we believe, improvement, is still in progress. In the “Théorie Elementaire de la Botanique" of De Candolle, published in 1819, the number of orders then given was one hundred and sixty-one. In the Prodromus before us, as far as published, the first sixty-six orders bave been, by subdivision and by the interposition of new orders, extended to ninety, so that they will, probably, exceed two hundred before the prodromus shall be completed, and even of the orders as published in this work, many might still, we think, have been advantageously divided.* We have long held the opinion, limited as our opportunities of judging have been, that the families in this system must approach five hundred, before it will form a perfect and consistent exhibition of the vegetable kingdom. We think on this question there should be no compromise. No argument ab inconvenienti, should be permitted to interfere with an arrangement professing to be based on fixed and determinate principles. Every plant which has no associate in any estab
Let the Nelumboneæ and the Nymphiaceæ—the Cleomeæ and the Cappareæ-the Violeæ and Sauvageæ--the tribes of the Byttneriaceæ, and of the Terastroemiaceæ, to go no further, be accurately compared.
lished order, ought, however it may lead to the multiplication of these divisions, to have a place of its own.
If we now for a moment advert to the principles of this system, it will appear that it is not so much to any one feature or character, as to the judicious combination of many, that it is indebted for its excellence. Yet its leading and essential principle is, after all, one of secondary value. It is not derived from the embryo itself, its structure, form and position, but on the cotyledons, the special organs with which the embryo is furnished, to aid in its developement. The absence or presence of this organ forms two large or primary divisions; while among the plants possessing this organ, the number, one, two or many, still constitutes further marks of separation; the position and direction of the embryo, the perisperm and other peculiarities of the seed break again these large masses. Still, however, the plants in each division are far too numerous and dissimilar, and all the known and used characters of the seed will not separate them into well-defined orders. The position of the stamens, the presence or absence of a corolla, its structure where present, the presence or absence of a calix, are all called in to subdivide to a sufficient degree, the whole vegetable kingdom, and to collect into distinct groups, those which have features truly uniform, and easily recognised. Will human researches lead no further? Will the profound investigations of nature never carry our knowledge to those deep-seated and mysterious principles, which, existing in the embryo, possess within themselves, even from the dawn of existence, before the unfolding of the first organs of active life, the perfect archetype of all their future forms and modes of being. Even in the germ, the future ens, whether plant or animal, perfect, but not yet sensible to our eyes or our understandings, exists in beautiful, though veiled and hidden symmetry. In every seed the distinct image, with all its peculiar and appropriate characters, is present, and with a clearer ken than we now possess, might be perceived at one view, and not ascertained, as with us, by its slow and gradual developement. Will the glorious discoveries of science never go back to those obscure and secret types ? Will man never be permitted to view, even in their first elements, the arrangements of all created forms; in their first movements, the adaptation of all beings and parts of beings to their appointed ends; and to trace to their final results, the beneficent and sublime barmony of nature.
The work we have prefixed to this article, is the first great effort wbich has been made to arrange all the known plants of the globe, according to the system of Jussieu. It is upwards of