but only some trace of resemblance in the organisation, which may be found also in a number of very different plants.

Linneeus was endowed with too sound a judgment, with a tact too exquisite, not to feel the defects of this artificial mode of classification. He detected by the force of his genius the existence of vegetable groups superior to genera, and connected them by a large number of characteristics. He called this group a natural order, and it has since his time been called the “natural family.” He also tried to distribute plants after a natural classification—that is to say, into families. After the death, and during the life, of Linnzus, botanists endeavoured to discover upon what principle he had founded his natural orders—that is to say, they sought to find the key to the hidden principle of his orders; but no one has succeeded. Linnaxus

é himself does not appear to have had very fixed views on the subject. He created his orders by a sort of instinct which belongs only to the man of genius; by that kind of semi-divination which the man of learning acquires who possesses vast and profound knowledge of the objects which he passes his life in observing. Linneus created his natural orders, then, without any well-premeditated plan, and without having compared any well-defined assemblage of organs; this is sufficiently proved by the following conversation with one of his pupils named Giseke, which has been preserved, and which we consider sufficiently interesting to repeat here, leaving the interlocutors to speak each for himself:—

Liynavus. Do you think, my dear Giseke, you are able to give the characters of any one of my orders? Gisexe. Yes, without doubt; for example, that of the umbellifera.

Linnzvus. Well, what of it?

Gisexz. That is true, I recollect some. I will add the two naked

Livnxvs. Not at all; it is most certainly an umbellifera, for it has an involucré, five stamens, two pistils. What then shall be its character?.

Gisexe. Such plants ought to be placed at the end of an order where they ™ / bridge over the passage from one to another. The Eryngiwm would thus connec the Umbellifera with the Aggregata. Livzvs. Oh, no, that is quite another thing; it is one thing to know the

passages between, and another to describe the characters of two groups. I know them very well, and how the one ought to be joined to the other. One of our former pupils, :: F

ell you one thing,—if I publish a second edition of my book, I shall give a second arrangement of my orders. ‘Ina letter to the same botanist, we find the following passage: “You ask me for the characters of my orders. My dear Giseke, I assure you that I know not how to give them.”

1 7% \ Vite / Af ei y, 4/ we / Vy ef Jit @ tiv

Fig 289.—Mugnol. DM. Magnol, Professor of Botany to the School of Medicine, in his work entitled « Prodromus Historiz Generalis Plantarum,”

S065 a THE VEGETABLE WORLD.

is the first author who uses the happy term “ family ” to designate natural groups of vegetable genera. M. Florens speaks of

eult problem. The following lines are taken from this much admired preface: “ Having examined the methods most in use,” | says Magnol, “and found that of Morison insufficient and very defective, and that of Ray much too difficult, I think I can ‘perceive in plants a certain.affinity between them, so that they might be — ranged in divers families, as we class animals. This apparent © analogy between animals and plants has induced me to arrange them in certain families, and, as it appeared to me impossible to draw the characters of these families from the single organ of-fructification, I have selected principally the most noted characteristics I have met with, such as the root, the stem, the flower, the seeds. There is also found among plants a certain similitude, a certain affinity, as it were, which does not exist in any of the — parts considered separately, but only as a whole. I have no ~ _ doubt, for instance, but that the characters of families might be _ "taken from the~first TeafOf-the germ as it:issued from-the sevd. I have followed the order that protects the parts of plants in which are found the principal and distinctive family marks, but without limiting myself to any one single part; for I have often — considered many of them together.” ra Magnol established seventy-six families, but without giving their characters. His principles of classification are vague and uncertain; they only serve to announce the dawn of anew day | which was soon to rise on the science. The few lines which we | have quoted from the preface of the ‘ Prodromus” reveals, 3 pe through a fog, the mere idea of a natural system. It is Bernard de ao Jussieu, Demonstrator of Botany in the Jardin des Plants at Paris, © a to whom belongs the glory of working out the true natural system | which was first established in principle by Ray, although it does — not appear that Jussieu was acquainted with the works of the | English philosopher. + Bernard de Jussieu, as his nephew Laurent de Jussieu tells 0, — regarded botany, not as a science of memory or nomenclature, but as a science of combination, founded on a profound knowledge of

the characteristics of each plant. He would every day get together the materials out of which he had to form his natural orders, which he regarded as the “ philosopher’s stone” of botanists. He deferred the publication of his first Essay in his zeal and desire to perfect his work. He wrote little, but observed much, and the

fruits of his labour would perhaps have been lost to science but °r a favourable circumstance which obliged him to give his ie od of arrangement of plants to the world. Louis XIV. aving seen the gardens of Saint Germains, in which the

Marshal Duke de Noailles cultivated exotic trees and shrubs, formed the design of creating a School of Botany at Trianon. By the advice of Lemonnier, chief physician to the Child of France, afterwards King, he selected Bernard de Jussieu to arrange the rdens. Thus forced to adopt some mode of classification, he thought it his duty to substitute his new method. This method consisted in having a tableau raisonné on which the plants were arranged in a conyenient order for studying them. Science confined to such narrow limits is, however, very fictitious, and remote from a natural system, which consists in the knowledge of the true connection of plants and their organisation. “ When of plants,” says Laurenta man has so combined the characteristics de Jussieu, “that he can in one species unknown determine the existence of many by the presence of a single character; when he can at once point to the order to which it belongs; when he has succeeded in destroying the prejudice so withering to Botany, that it is only a science of memory and nomenclature; when he has, in short, founded a science of combinations which furnish food to the mind and to. the imagination, that man may surely be called the creator, or at least the restorer, of science.”

“Others may perhaps have extended the limits, but he was the first to show the way, to trace the method, establish the principles. Jussieu consignedhis discoveries to no book, but in the Gardens of Trianon the mind of the author is recognised. In examining the characters, he remarked that some were more general than others, and these furnished the first division. Having appreciat and appropriated these, he next recognised that the germination of the seed and the respective disposition of the sexual organs ware He adopted the two principal and most persistent characteristics. them, and made them the basis of the arrangement which he established at Trianon in 1759.”

Four years later, another French botanist, Michel Adanson, *: naturalist, remarkable for the originality of his views and the extent of his conceptions, published quite a book upon the families of plants. He proposed a particular course for arriving pe true natural method. But what was that course? He pro classing all the plants known according to a great number possible:: artificial systems, and after considering them from all

points of view; he proposed to arrange in the same group those plants which were classed as allies in the greatest number of systems. In this manner Adanson created sixty-five artificial systems, and by their comparison, he formed them into fifty-eight families. He was the first to trace the precise characters and details of all these families;his work in this respect is far superior to those

Fig. 291.—Ad anson, if Michel Adanson was right Neverthelessof his predecessors, these plants, in classifying characteristics all their“employing importance the same in giving hand, other on the Motay ce considering that without characters up the reckoned “» le P

they were not all of equal value. The results of his calculations were frequently found to be false, as would inevitably happen with any sum where no regard was paid to the quality of the metal, but only to the shape and volume of the coin. oe

The year 1789 was the date of the true creation of natural families among vegetables. It was about this time that Laurent — de Jussieu published his celebrated “Genera Plantarum,” which — raised the science of botany, and marked a new era, not only in vegetable science, but in the classification of animals.

The catalogues of the Gardens of the Trianon, prepared by Bernard de Jussieu, and the conversations of the latter with his nephew, were the primitive spark whence the latter drew his inspiration. — We shall, however, leave his grandson, Adrien de Jussieu, to state the true basis of the Natural System, and the considerations which guided his relation. “Like Adanson,’’ says Adrien, “ Antoine- Laurent de Jussieu admits that the examination of all parts of a

plant is necessary in order to its classification; but in pursuing this... 2 examination it is not sought to deduce theoretically the combination of the genera; thus in grouping them into families, he imitated the proceedings followed in the formation of the genera themselves. The botanist, struck by the complete and constant resemblance of certain individual plants, formed them into species; then, observing a resemblance equally constant, but much less perfect, he formed — them into genera. The characters, which might vary evenin the = same species, ought to depend on causes exterior to the plant, amd not on the plant itself: for example, its size, consistence, certain modifications of form and colour, which we see change with the = sun, the climate, and under other influences purely circumstantial. The specific characters, on the contrary, those especially which | every, individual should possess, as belonging to certain species; whatever be the circumstances in which they are found, ought to hold to the nature of the plant. Among these characters some are oe: more important than others, and less subject to variation. Finding these characters in a certain number of species marks what constitutes a genus. These would, from their general nature, have. more value than the specific, as the specific is of more value than the individual characteristics, — “ But how are we to discover and estimate these different values? _

~ ature herself indicates to the observer the species and many of _ e genera, by the- features of resemblance with which she marks —

Jussieu thought that the key to the ul method was there; since, in comparing the character of one those families with the genera composing it, he would obtain a 10owledge of the relation of one to the other; and in comparing any among them, he would see how the characters common to all ants of the same family varied one from the other; he would Us arrive at a true appreciation of the value of each character, idthis value, once determined by means of groups so clearl gned by nature, could be applied in its turn to the deter-mation of others which were not so strongly impressed with the y Seal; others which were the unknown in the great problem. Bslacted for this purpose seven families already universally cognised;those, namely, known as the Graminacem, the Filiacese,

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