l-'l 



BOTANY. 



BOTANY. 



002 





from the whole he deduced a classification which is unquestionably 

 the basis of that which, under the name of the system of Jussieu, is 

 everywhere recognised at the present day. For proofs of this we refer 

 to the memoir of RAY in the HIST., BIOG., &c. DIVISION. We will 

 only observe here that he separated flowering from flowerless plants; 

 that he divided the former into monocotyledons and dicotyledons, 

 and that under these three heads he arranged a considerable number 

 of groups, partly his own, partly taken from Lobel and others ; which 

 are substantially the same as what are received by botanists of the 

 present day under the name of natural orders. It is singular enough 

 that the merits of this arrangement of John Ray should have been so 

 little appreciated by his contemporaries and immediate successors as 

 to have been but little adopted ; and that instead of endeavouring to 

 correct its errors and to remove its imperfections, botanists occupied 

 themselves for several succeeding years in attempts at discovering other 

 systems, the greater part of which were abandoned almost as soon as 

 they were made known. Rivinus, Magnol, Toumefort, and Liunteus 

 were the most celebrated of these writers ; but the two last alone 

 have had any permanent reputation. Tournefort, who for a long time 

 stood at the head of the French school of botany, proposed in 1694 a 

 method of arrangement, in its principles entirely artificial, but which 

 in some cases was accidentally in accordance with natural affinities. 

 It was founded chiefly upon differences in the corolla, without the 

 slightest reference to physiological peculiarities ; and is now forgotten, 

 except in consequence of its having furnished some useful ideas to 

 Jiuwieu, as will be hereafter shown. 



The Fifth Era. Lmmeiu was a genius of a different and a higher 

 order. Educated in the severe school of adversity, accustomed from 

 his earliest youth to estimate higher than all other things verbal accu- 

 racy and a logical precision, which are often most seductive when least 

 applicable ; endowed by nature with a most brilliant understanding, 

 and capable, from constitutional strength, of any fatigue either of 

 mind or body, this extraordinary man was destined to produce a revo- 

 lution in botany, among other branches of natural history, which in 

 some respects advanced and in others retarded its progress far more 

 than the acts of any one who had preceded him. He found the 

 phraseology bad, and he improved it ; the nomenclature was awkward 

 and inconvenient, he simplified it ; the distinctions of genera and 

 species, however much the former had been improved by Tournefort, 

 were vague and too often empirical he defined them with an appa- 

 rent rigour which the world thought admirable, but which nature 

 spurned ; he found the classifications of his day so vague and uncer- 

 tain that no two persons were agreed as to their value, and for them 

 he substituted a scheme of the most specious aspect, in which all 

 things seemed as clearly circumscribed by rule and line as the fields 

 in the map of an estate ; he fancied he had gained the mastery over 

 nature, that he had discovered a mighty spell that would bind her 

 <!owii to be dissected and anatomised, and the world believed him ; 

 in short, he seized upon all the wardrobe of creation, and his followers 

 never doubted that the bodiless puppets which he set in action were 

 really the divine soul and essence of the organic world. Such was 

 Linnaeus, the mighty spirit of his day. Let us do this great man 

 that justice which exaggeration on the one hand and detraction on the 

 other have too often refused to him, and let us view his character 

 soberly and without prejudice. We shall then admit that no natu- 

 ralist has ever been his superior ; and that he richly merited that high 

 station in science which he held for so many years. His verbal accu- 

 racy, upon which his fame greatly depends, together with the remark- 

 able terseness of his technical language, reduced the crude matter that 

 was stored up in the folios of his predecessors into a form that was 

 accessible to all men. He separated with singular skill the important 

 from the unimportant in their descriptions. He arrayed their endless 

 synonyms with a patience and lucid order that were quite inimitable. 

 By requiring all species to be capable of a rigorous definition not 

 exceeding twelve words, he purified botany of the endless varieties of 

 the gardeners and herbalists ; by applying the same strict principles 

 to genera, and reducing every character to its differential terms, he 

 got rid of all the cumbrous descriptions of the old writers. Finally, 

 by the invention of an artificial system, every division of which was 

 defined in the most rigorous manner, he was able so to classify all the 

 materials thus purified and simplified that it seemed as if every one 

 could become a botanist without more previous study than would be 

 required to learn how to discover words in a dictionary. Add to all 

 this the liveliness of his imagination, the skill with which he applied 

 his botanical knowledge to practical objects, and the ingenuity he 

 showed in turning to the purposes of his classification the newly- 

 discovered sexes of plants, and we shall at once comprehend what it 

 was that exalted Linmcus so far above his contemporaries. But great 

 as the impulse undoubtedly was which Linnaeus gave to botany, there 

 were vices in his principles which although overlooked during his life 

 have subsequently been productive of infinite evil. There is no such 

 thing as a rigorous definition in natural history ; this fact Ray had 

 demonstrated to arise out of the very nature of things ; and conse- 

 quently the short phrases by which species and genera were charac- 

 terised liy Limiii-iifi were found equally applicable to many other plants 

 In ^iili s those for which they were intended : hence arose a new source 

 of confusion, inferior only to that which it was intended to correct. 

 Differential characters, which would be invaluable if we had all nature 



before us, were found in practice to lead to incessant errors, so soon 

 as some new species was introduced into the calculation : they also 

 laboured under the great fault of conveying no idea whatever of the 

 general nature of the plants to which they related : thus the Portu- 

 guese botanist Loureiro, who attempted to determine the plants of 

 China by the systematic writings of Linnaeus, fell into the singular 

 error that the hydrangea was a primrose. With regard to his artificial 

 system of classification, it was found that it looked better in the closet 

 than in the field ; that the neatness and accuracy of the distinctions 

 upon which it was divided into groups existed only upon paper, and 

 that exceptions without end encumbered it at every turn. This, which 

 is perhaps inseparable from all systematic arrangements, would not 

 have been felt as so great an evil if there had been any secondary 

 characters by which the primary ones could be checked, or if the 

 system had really led with all its difficulties to a knowledge of things. 

 But it was impossible not to perceive that it led in reality to little 

 more than a knowledge of names, and that it could be looked upon as 

 nothing beyond an index of genera and species. 



The maxims however of Ray, and the great general views of that 

 illustrious naturalist, were destined not to fade even before the 

 meteoric brilliancy that surrounded the throne of Linuseus. A French 

 botanist, Antoine Laurent de Jussieu, soon entered the field to oppose 

 the latter. In the year 1789, just eleven years after the death of Lin- 

 naeus, he produced under the name of ' Genera Plantarum ' an arrange- 

 ment of plants according to their natural relations, in which the 

 principles of the great English botanist are tacitly admitted, and his 

 fundamental divisions adopted, in combination, in part with those of 

 Tournefort, in part with those which had been proposed by Adanson 

 in his remarkable work on the ' Families des Plantes,' and the rest 

 with what are peculiar to the author himself. Jussieu possessed in a 

 happier degree than any man that has succeeded him the art of 

 adapting the simplicity and accuracy of the language of Liuuaaus to 

 the exigencies of science, without encumbering himself with its 

 pedantry. He knew the impossibility of employing any single charac- 

 ters to distinguish objects so variable in their nature as plants ; and 

 he clearly saw to what evils all artificial systems must of necessity 

 give rise. Without pretending then to the conciseness of Linnaeus in 

 forming his generic characters, he rendered them as brief as was con- 

 sistent with clearness ; without peremptorily excluding all distinctions 

 not derived from the fructification, he nevertheless made the latter 

 the essential consideration ; instead of defining his classes and orders 

 by a few artificial marks, he formed them from a view of all the most 

 essential parts of structure ; and thus he collected under the same 

 divisions all those plants which are most nearly allied to each other. 

 Hence, while a knowledge of one plant does not by any means lead to 

 that of another in the system of Linnaeus, it leads directly to the 

 knowledge of many more in the classification of Jussieu, which has 

 accordingly gained the name of the ' Natural System.' This at once 

 brought the science back to a healthy state ; it demonstrated the pos- 

 sibilty of reducing the characters of natural groups to words, contrary 

 to the opinion of Linnasus, who found that task altogether beyond his 

 powers ; it did away with the necessity of artificial arrangements, and, 

 giving a death-blow to verbal botany, it laid the foundation of that 

 beautiful but still imperfect superstructure which has been erected 

 by the labours of Brown, De Candolle, Lindley, and others. If the 

 system of Jussieu were not a return to that of Ray, modified only and 

 improved by modern discoveries, we should certainly have taken this 

 period for the commencement of 



The Sixth and latest Era in our science. But it was reserved for a 

 man whose fame lies chiefly in the literary world to effect the last 

 great revolution that the ideas of botanists have undergone. In 1790, 

 one year after the appearance of Jussieu's ' Genera Plantarum,' the 

 German poet Gothe published a pamphlet called ' The Metamorphosis 

 of Plants.' At that time the various organs of which plants consist 

 had been pretty well ascertained, the distinctions between the leaf, 

 the calyx, the corolla, the stamens, and the pistil were in a great 

 measure understood, and the botanists were not a few who fancied 

 there was nothing more to learn about them. Nevertheless even in 

 the time of Theophrastus a notion had existed that certain forms of 

 leaves were mere modifications of others that appeared very different, 

 as the angular leaves in croton of the round cotyledons or seminal 

 leaves of that plant. Linnaeus himself had entertained the opinion 

 that all the parts of a flower are mere modifications of leaves whose 

 jH'rioil of development is anticipated ('Prolepsis Plantarum'); Ludwig 

 in 1757, and more especially Wolff in 1768, had stated in express 

 terms that all the organs of plants are reducible to the axis and its 

 appendages, of the latter of which the leaf is to be taken as the uni- 

 versal type. But the theory of Linnaeus was fanciful ; Ludwig was a 

 writer of too little authority in his day to succeed in establishing a 

 doctrine so much at variance with received opinions ; and the theory 

 of Wolff was propounded in a paper upon the formation of the intes- 

 tines in animals, which seems altogether to have escaped the observa- 

 tion of botanists. Entirely unacquainted with the writings of the two 

 latter naturalists, but aware of the ' Prolepsis Plantarum ' of Linnaeus, 

 Giithe took up this important theory, and demonstrated that all those 

 organs to which so many different names were applied, and which in 

 fact have so many dissimilar functions to perform, Were all modifica- 

 tions of one common type the leaf; that the bract is a contracted 



