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productive of no greater inconvenience to those that remain, y continually rooted to the same spot, which have no power than the swarming of bees is to their parent hive.
of roaming from place to place in search of aliment, which It is obvious therefore that they in reality bear a close have no capability of distinguishing between the useful analogy to corals and polypes; and this leads us to the and the hurtful, the wholesome and the poisonous, but inquiry as to how plants differ from the animal kingdom. which are compelled to derive their support from such
If animals consisted only of quadrupeds, and birds, and matter as chance may place immediately and continually fishes, and vegetables were confined to trees and herbs, no in contact with them, and which therefore experience no conceivable difficulty of assigning to each kingdom the most cessation to the supply of food, are not provided by nature positive limits could be experienced. For every person with organs of mastication. The want of these organs sees how wide a difference exists between the larger ani- renders a stomach unnecessary; internal absorption or inmals and the more conspicuous plants: the less indeed we tussusception of nutriment cannot take place; and we acare acquainted with the subject, the more easy is the task cordingly find that their existence is sustained not by an of distinguishing them; but to those who are acquainted uncertain periodical introduction of food into an internal with the infinite varieties of form, structure, and nature, cavity, but by the perpetual absorption of food from the which are included within these kingdoms, the limits which matter perpetually about them, through pores of their divide them will be found to present one of the most difficult surface too fine for human perception. Nothing therefore problems in the philosophy of natural history.
which requires to be divided by mechanical force, nothing As an ingenious French physiologist has well remarked, which needs to be altered in its texture or substance before it is not a question about what are the characters peculiar it can be used, or to be digested, nothing which has to be to animals, but what are common to them all. We know sought for, nothing in short but matter which is so delicate very well that they only have brain, nerves, muscles, a as to pass through perforations, which the human senses, heart, lungs, a stomach, and a skeleton; that they move, aided by the most powerful microscopes cannot distinguish, digest, respire; that they have blood, and appear to have is fitted for the support of plants; and no inorganic matter sensation ; but what remains of all these characters when exists which answers to this description, but water or air, or we descend the long chain that they form, from the first link substances held in solution by these two elements, and to the last. Almost nothing. Lungs, glands, brain, ske- such in fact are the materials by which vegetables are supleton, heart, arteries, blood, nerves, and muscles, succes- ported. sively disappear, till at last we are not sure whether we have As in animals, nourishment is derived from their centre, even a stomach left. (Isid. Bourdon, Phys. compar. p. 10.) so it follows that all their absorbent vessels have a direction
If a comparison is instituted between the highest form towards that centre; and for the same reason, as in plants, of development in either kingdom, between a human being nutrition is communicated from the outside, so is it in that and a tree, the differences are too striking to escape the direction that all the absorbent vessels of the vegetable are most ordinary observation. We see that animals are en- directed. The consequence of these two laws is, that while dued with sensation or perception; that they possess loco- a term is prescribed to the growth of the most perfect animotivity, or the power of transporting themselves from place mals, no limit seems to be fixed for that of the most perfect to place; that they live upon organic substances which their vegetables. The former perish as soon as their original vespowers of locomotion and perception enable them to select ; sels become incapable of performing their functions ; the that their food passes through an alimentary cavity, from latter endure until the power of forming new vessels shall which its nutritive properties are transfused by means of cease. The period to the former is fixed, to the latter unabsorbent vessels into the system. Plants, on the contrary, limited. Hence an eloquent French writer has ingeniously are destitute of all traces of a nervous system and conse- said, that animals die of old age or accidents, vegetables of quently of perception; they are fixed to a particular spot accidents alone. Hence also the incredible age to which whence nothing but mechanical power can remove them ; certain trees arrive. The cedars of Mount Lebanon are said they are incapable of all motion, except from some internal to be of an antiquity far beyond all history; and it has been mechanical agency; they subsist upon such inorganic mat- calculated by a French botanist, from actual inspection, that ter as surrounds them, and their food is at once introduced the age of the baobab trees of Senegal must have exceeded into their system by absorption through their external surface 6000 years. These are the most decided differences between only.
animal and vegetable life, and are almost without exception. Vegetables are also said to be compound beings, animals Some plants, indeed, having only an annual or biennial exsimple beings. For illustration, whatever objections may istence, have a term fixed to their lives, just as animals be taken to such a comparison, the latter may be considered, have, but no plants can be pointed out in which nourishwith Link and Blumenbach, to have only one seat of life, the ment does not take place from the outside. When we desensorium commune, and to have but one provision made scend in the scale of being, when we arrive at those limits by nature for their propagation ; the former, which are ca of the world where life first arises out of death, in which pable of reproduction by various means from various points sensation is indistinguishable, and from which the two kingof their body, must have the seats of vitality as numerous as doms seem to diverge as from a common point, even there the parts which are thus capable of self-perpetuation. Hence we find the polypes, which are so simple in their structure articulations, buds either latent or developed, and seeds, are that they may be turned inside out like a glove, always conin plants so many distinct seats of vegetable life. While forming to this law. Zoologists assure us that they still all-powerful man has but one feeble means granted him of absorb from the inside even when that part of the body perpetuating his race, millions of millions of individuals, which was once the outside has to perform the duties of a which in a physiological sense are identically the same, stomach. have been produced by the half-dozen potatoes brought to But with this exception we know of no absolute external Europe by Raleigh, in 1584, and this without any aid from distinction which has yet been discovered between animals the ordinary means which nature has given plants for their and vegetables. The ingenious idea of Mirbel, that animals multiplication.
live upon organic, vegetables upon inorganic matter, must, Among the distinctions between the animal and vegetable as respects the infusorial animalculæ, be a purely hypokingdom, that which demands the first consideration is the thetical difference, and in more perfect animals is not true, different means possessed by animals and vegetables of pro as has been shown by Mr. William MacLeay, who asserts curing food and of imbibing nourishment. Animals have that many animals of the lower tribes, and some Heterothe power of moving from place to place, and are gifted merous Coleoptera, have been observed to feed upon inwith perception, which enables them to distinguish what is organic matter.' (Hor® Entomologicæ, ii. 193.) proper for their sustenance. They are also furnished with If we now reconsider the observations which have just organs of mastication, which enable them to reduce to mi- | been made, and endeavour to see to what the distinction of nute pieces very hard substances. As their food is only pro- animals and vegetables is really reducible, we shall find that cured by an act of exertion on the part of the animal, and as it consists in animals being organic beings, possessed of this exertion is not continuai and uninterrupted, but only sensation and locomotion, and sustained by the abscrption takes place at intervals of time, they are also provided with of nutriment through an internal canal, while plants have an internal reservoir in which the food that is so procured is no sensation or locomotion, and are nourished by absorption deposited; from this reservoir, called the stomach, the ab- through their cuticle. But how are we to apply these dissorbent vessels conduct the elaborable parts into the system, tinctions to the lower orders of created beings? Among while the solid useless parts are rejected : animals therefore these we find productions, which it is impossible, by the are nourished by internal absorption. Vegetables which are characters now assigned, to refer with any exactness either
to the one kingdom or the other. A drop of water and a To which kingdom are we to refer the beautiful Sallittle brown or green slime from a ditch will often afford macis and all the tribe by some botanists called Confervæ abundant evidence of the accuracy of this remark.
conjugata, or Zygnemas, which Messrs. Gaillon and De If we place a drop of water and a few fragments of con Blainville assert to be of animal nature, but which grow fervæ under a microscope, we shall probably discover an like vegetables, from which they are undistinguishable by abundance of little bodies shaped like a weaver's shuttle, external characters. They are transparent tubes, having transparent at the extremities and in the middle, with two distinct articulations and transverse partitions, the cavity or four semi-opaque brownish cavities in their inside : these being filled with brilliant green spherules arranged with the bodies have a sort of starting motion, very distinct and con most beautiful symmetry in one or more spires, which, tinued, but they do not seem capable of turning on either separating at a certain period of their existence, and passing axis ; nor is any motion of contraction visible; they vary in through the sides of the tube, develop in the form of new length, according to De Blainville (Dict.des Sc. Nat.34, 367), tubes exactly like their parent. When in a perfect state from the five-hundredth to the hundredth of a line, and the contiguous tubes or filaments unite in a manner comwhen full grown exceed these dimensions considerably. By pletely animal in appearance, uniting at one period, sepaMüller, a standard writer upon infusorial animalcules, they rating at another, and finally combining themselves into are considered animals, and referred to his genus Vibrio, a single and uniform being. part of which consists of bodies of an undoubted animal Lastly, where are we to place the oscillating confervæ, nature. By modern observers they have been named Navi- those slime-like masses which cover the earth in damp and cula. When young they are attached to confervæ by a shady places, or form mucous patches among the conferva stalk so delicate as to be almost invisible with the aid of the and polypes of stagnant water, or appear under the form of most perfect microscopes, and during this period they have, a rich carmine stain, bordered with resplendent violet and according to M. Bory de St. Vincent, no visible motion blue, on the surface of hot springs, in all parts of the world; whatever ; but when the Navicula is fully formed it sepa- productions which, according to the speculations of an ingerates from the plant on which it grew, swimming and start- nious Swedish naturalist, have once possessed an animal ing about in the water in the way described. Are such life, of which they now only retain the appearance. These productions animal or vegetable ? When young they are oscillatorias consist of articulated tubes filled with green motionless and vegetable like a minute plant; when full | granules, and grow and increase like confervæ, and the regrown they acquire the movement of animals. Perhaps one productive particles to which they give birth have no momay say they are the latter, and compare their vegetating tion that is apparent. But the tubes themselves have a state when young to that of the Polype, called Vorticella, an writhing, twisting, undulating, creeping, distinctly animal undoubted animal, if rapid and varied motion can make it so. motion, which it is impossible to mistake; they are more
Among confervæ in ditches are often found little frag- active in warm than in cold weather, and in the latter can ments of organized bodies; some like ribbands, separable be excited to action by the application of warmth. When completely into numberless narrow transverse portions, chemically examined, they have been found to exhibit many others dividing partially at their articulations, but ad- of the characters peculiar to the animal kingdom; and hering at their angles like chains of square transparent when burnt, yield a carbon of the most fetid odour, exactly cases. These enter the genera called by naturalists Dia- resembling that of decaying animal substances. toma, Fragilaria, Exilaria, Achnanthes. Are they animals Such are a few of the difficulties which that naturalist has or plants ? When combined they are motionless, with to overcome who would fix the limits between the animal all the appearance of confervæ, their transparent joints and vegetable kingdoms. It is clear that the power of filled with' the green reproductive matter of such plants ; voluntary motion exists in beings having a distinctly vegebut when they disarticulate, their separate portions have a table structure, both in the most perfect state and in a state distinct sliding or starting motion. Shall we call them, with of disintegration; that the absorption of nutriment from M. Gaillon, chains of animals assembled in a voluntary cap- the inside in the one family, and from the outside in the tivity which no one has seen them assume; or shall we not other, is a character not appreciable in such creatures as the be rather justified in viewing them as links between the monads, and the vivifying animalcules of flowering plants; animal and vegetable kingdoms, and endowed with the cha- and, finally, that chemical differences are destroyed by anaracters of both.
baina and oscillatorias. In this difficulty shall we admit, Conferva mutabilis, or Draparnaldia, is a plant-like body, with M. Bory de St. Vincent, a new kingdom intermediate which, according to Messrs. Mertens and Gaillon, is some- between animals and plants, characterized as consisting of times an animal, sometimes a plant. The former says that insensible individuals, that develop and increase in the he has frequently seen it undergo its transformation, parti- manner of vegetables, up to the period when they separate cularly in August, 1822. On the 3rd of that month he into animated germs or reproductive fragments; or shall showed it to a great number of persons in a state of plant ; not we rather consider the absence of all exact limits beon the 5th it had disarticulated into portions distinctly mov tween animal and vegetable nature as a striking proof of ing in water, which on the 6th began again to unite, and on the beautiful harmony of nature, and of that unity of purthe 10th became finally combined into their primitive state pose which is so visible in all the works of the Creator; as of conferva. (Dict. des Sc. Nat., 34, 373.)
an evidence that all the forms of life are but assemblages It perhaps may be said that the instances yet given are in insensible gradation of the same living matter differently not at variance with the distinction of animals and vegeta- combined by the great Spirit that pervades all matter and bles by their power of motion; and that as they are all inert all space ? when in their most perfect state, their giving birth to moving II. In treating of the history of this science, we have no bodies does not make them animals any more than the pro- intention of entering upon details which can only interest duction of motionless eggs by birds, reptiles, and mollusca the systematical botanist, or of criticising every siep which makes them vegetables.
its followers may have taken; but, on the contrary, we shall In which kingdom then are we to station the curious Poly- confine ourselves to a mere sketch of the progress that has physa, a most undoubted polyp, according to Lamouroux, been made in elucidating the great principles by which its teman, and De Blainville; an equally certain plant if we rank as a branch of philosophy is to be determined. are to believe Turner, Agardh, and Gaudichaud, the last of It is obvious from various passages in the most antient whom found it living, and describes it thus. It grows in thick writers, that the art of distinguishing certain plants having tufts to the shells which are thrown ashore upon the barren medical virtues was taught at the earliest period of which coast of Shark's Bay in New Holland. Each individual we have any written record; and that the cultivation of consists of a fistular, capillary, greenish stalk, about an inch something more than corn was already understood in the or an inch and a half long, expanding at the base into a Homeric days is sufficiently attested by the references to sort of root-like claw, by which it is fixed. At the end it the vineyards of Laërtes and the gardens of Alcinons, and bears from fifteen to eighteen sacs, which are entire, rounded by the employment assigned to Lycaon, the son of Priam, at the end, and slightly attenuated to the base ; each con- of pruning figs in his father's garden. tains a multitude of little round green globules, which The earliest tangible evidence that we possess of the real finally expand and break through the thin case in which state of knowledge upon this subject is afforded by the rethey are included. They are filled with a green unctuous mains of the writings of Aristotle and his school. From the matter, and the colour of the parent body is entirely due to absurd superstitions of the root-cutters (rhizotomi) of this their presence, for when they have all escaped from their period it might be imagined that at this time botany was far sacs, the mother body is perfectly colourless.
from having any real existence; for it is to them that we
have to trace the belief in the necessity of magical ceremonies precise for the words of a poet; and although to these and personal purification or preparation in collecting herbs; operations were attributed powers which they did not possome sorts, they tell us, are to be cut against the wind, others sess, yet it is abundantly plain that the processes were after the body of the rhizotomist has been well oiled, some at thoroughly understood. The night, some by day. Alliaceous food was a necessary prepara
Angustus in ipso tion for procuring this herb, a draught of wine for that, and
Fit nodo sinus; huc aliena ex arbore germen so on. But in fact at this very time the Peripatetic philoso
Includunt udoque docent inolescere libru, phers were in possession of a considerable mass of correct is as correct a description of the operation called budding as information concerning the nature of vegetable life, mixed any modern could give in so many words; and it is imposup indeed with much that was fanciful and hypothetical, sible that such an operation should ever have been devised but calculated to give us a high opinion of their acuteness without a much more large and accurate knowledge of and of the amount of positive knowledge upon such sub- vegetable physiology than it is generally believed that the jects which had by that time been collected. It is by this antients possessed. school that botany must be considered to have been first From this time forward all inquiry into matters of science formed into a science. Aristotle, in all probability, was its began to decline ; under the later Roman emperors science founder ; for it is obvious from the remarks upon plants became gradually extinguished; under the Byzantine princes scattered through his books concerning animals
, that his it can scarcely be said to have been preserved, and the little knowledge of vegetable physiology was, for his day, of a attention it subsequently received from a few obscure writers most remarkable kind. But as the books immediately con- rather hastened than arrested its downfall. cerning plants ascribed to this philosopher are undoubted Upon the revival of science in Europe the writings forgeries, it will be more convenient to take the works of of the classical and Arabian herbalists were taken as the Theophrastus as our principal guide to a determination of text-books of the schools, but their errors were multiplied the state of botany at the commencement of this
by false translations, their superstitions were admitted withThe First Æra.-At the time when Theophrastus suc-out question, and so little was added by the monkish authors, ceeded to the chair of Aristotle (B.C. 324) no idea seems to that between the time of Ebn Beithar, who flourished in the have existed of classification, nor indeed was its necessity by thirteenth century, and the year 1532, when the Herbarum any means apparent, for Theophrastus does not appear to vivæ eicones of Otho Brunsfels, a Bernese physician, marle have been acquainted with above 355 plants in all.” In the their appearance, scarcely a single addition had been made application of their names, even to these, there was so much to the slender stock of knowledge of about 1400 species, uncertainty that the labours of commentators must be to a which are computed by Sprengel to have formed the total great extent bestowed in vain in endeavouring to elucidate amount discovered by all botanists, Greek, Roman, and them: for instance, Sprengel asserts that the name Aphake Arabian, up to the death of Abdallatif of Bagdad. Brunsis applied indifferently to the dandelion and to a kind of vetch fels describes the state of botany as being in his day most (Lathyrus aphaca), and Scorpios to a species of broom, to deplorable, as being principally in the hands of the most Arnica scorpioides, and to a kind of ranunculus. But while ignorant persons, and as consisting of a farrago of long and Theophrastus was thus careless in his denominations of spe- idle commentaries, disfigured by myriads of barbarous, cies, he has the great credit of having attended accurately obsolete, and ridiculous names.' He deserves to be mento differences in the organs of plants, to some of which he tioned as the first reformer in this science, and as the cargave new and special names; the form of leaves, their liest writer who earnestly endeavoured to purify the cormargin, the manner of their indentation, and the nature of rupted streams which had flowed through so many ages of the leafstalk, especially attracted his attention. He distin- barbarism from the antient Greek and Roman fountains. guished naked-seeded from capsular plants, and he demon- His example was speedily followed by Tragus, Fuchsius, strated the absence of all philosophical distinction between Matthiolus, and others; the knowledge of species rapidly trees, shrubs, and herbs, for he saw that myrtle-trees would augmented, partly by the examination of indigenous plants degenerate into shrubs, and certain oleraceous plants be- and partly by the remarks of the earlier travellers, who about come arborescent. Cellular tissue is spoken of as a sort of the year 1460 began to turn their attention to the vegetable 1lesh interposed between the woody tissue or vegetable fibre ; | kingdom; till at last their abundance became so great as to and even spiral vessels appear to be indicated under the name call for the assistance of compilers capable of digesting what of ines (ives): leaves are correctly said to have their veins had already begun to be scattered through numberless works. composed both of woody tissue and spiral vessels, and the The first undertaking of the kind was by Conrad Gesner, a parallelism of the veins of grasses is particularly pointed native of Zürich, who died in the year 1565. This excelout; palm-wood is shown to be extremely different from lent man spent the latter part of his life in collecting that of trees with concentric layers; bark is correctly di materials for a general history of plants ; he is stated to vided into liber and cortical integument, and the loss of the have caused above 1500 drawings to be prepared for the former is said to be usually destructive of life. The nutri- illustration of his undertaking, but, unfortunately, he died tive properties of leaves are clearly pointed out, and the before his project was executed, and his materials were power which both surfaces possess of absorbing atmospheric afterwards dispersed. He appears however to have brought nourishment. Some notion appears to have existed of the about one most important change in science, by discovering sexes of plants, contrary to the opinion of Aristotle, who that the distinctions and true nature of plants were to be denied them to the vegetable kingdom; in particular Theo- sought in their organs of reproduction rather than in those phrastus speaks of the necessity of bringing the male dates of nutrition. This was assuredly the first step that had into contact with the females, a fact which had been stated been taken forward in the science since the fall of the Roquite as clearly by Herodotus (i. 193) 100 years before ; but man Empire, and is abundant evidence of the great supeit is plain that he had no correct idea upon this subject, riority of Gesner over all those who had preceded him. for in another place he compares the male catkins of the From this time collections of species were made by numehazel to the galls of the Kermes oak.
rous writers; our countryman Turner, Dodoens, Lobel, These points are abundantly sufficient to show that among Clusius, Cæsalpinus, and the Bauhins, were the most disthe Peripatetics a considerable amount of tolerably exact tinguished writers between the years 1550 and 1600 ; and knowledge of botany really existed, and that a solid foun- among them the number of known species was so exceeddation had been laid for their successors.
ingly increased, especially by the discoveries of Clusius, And in fact it appears that the impulse they gave to in- that it became impossible to reduce them into any order vestigation did for some considerable time afterwards pro- without the adoption of some principle of classification, duce a perceptible effect; for by the time of Pliny it is Hence originated the first attempts at systematical arrangeevident that a considerable addition had been made to the ment, with which commences stock of botanical knowledge. It is true that it was much The Second Æra.-It is to Matthew Lobel, a Dutch phydisfigured by the poets, who then, as now, appear to have sician residing in England in the time of Elizabeth, that had only a smattering of the science of their day; but it is the honour is to be ascribed of having been the first to incredible that they should have been able to glean that strike out a method by which plants could be so arranged smattering out of any other field than a very rich one. For that those which are most alike should be placed next to example, the sexuality of plants, which Aristotle had de each other, or in other words which should be an expression nied, which Theophrastus had adverted to, is spoken of in of their natural relations. As may be supposed, this early positive terms; grafting, in more ways than one, and even attempt at the discovery of a natural system was exceedbudding, are spoken of in language which is remarkably ingly rude and imperfect; it is however remarkable for
having comprehended several combinations which are re- 1 subsequently required correction. From him physiological cognized at the present day: Cucurbitacea, Stellatæ, Gra- botany, properly speaking, took its origin. Clear and dismineæ, Labiatæ, Boragineæ, Leguminosa, Filices, were all tinct ideas of the true causes of vegetable phenomena gradistinctly indicated ; and it may be added that under the dually arose out of a consideration of the physical properties name of Asphodels he grouped the principal part of modern of the minute parts through whose combined action they are petaloid monocotyledons. The reasons however why such brought about; and a solid foundation was laid for the groups were constituted were not then susceptible of defini- theories of vegetation which subsequent botanists have protion; the true principles of classification had to be elicited by pounded : to Grew may also be ascribed the honour of having the long and patient study of succeeding ages. Among first pointed out the important difference between seeds the foremost to take up this important subject was Cæsale with one cotyledon, and those with two, and of having thus pinus, a Roman physician attached to the court of Pope been the discoverer of the two great natural classes into Sixtus V. This naturalist possessed a degree of insight which the flowering part of the vegetable kingdom is now into the science far beyond that of his age, and is memo divided. Grew, however, was no systematist; it was rerable for the justness with which he appreciated many of the served for another Englishman to discover the true prinless obvious circumstances which his predecessors had over-ciples of classification, and thus to commence looked. For example, he was aware of the circulation of The Fourth Æra.—John Ray, a man of a capacious mind, the sap; he believed that its ascent from the roots was of singular powers of observation, and of extensive learning, caused by heat; he knew that leaves are cortical expan-driven from his collegiate employments by the infamous comsions traversed by veins, proceeding in part from the liber; mands of a profligate prince, sought consolation in the study he estimated the pith of plants at its true value, and seeds of natural history, to which he had been attached from his he compared to eggs, in which there exists a vital principle youth. Botany he found was fast settling back into the without life; but he denied the existence of sexes in the chaos of the middle ages, partly beneath the weight of unvegetable kingdom. Improving upon the views of Gesner, digested materials, but more from the want of some fixed he showed how great is the value of the fructification in principles by which the knowledge of the day should be systematic botany; the flower he said was nothing but the methodized. Profiting by the discoveries of Grew and the wrapper of the fruit; the essential part of the seed he con other vegetable anatomists, to which he added a great store sidered to be what is called the corculum, that is the double of original observation, he in his Historia Plantarum,' the cone of plumule and radicle which connects the cotyledons. first volume of which appeared in 1686, embodied in one In general his views of vegetable physiology were much connected series all the facts that had been collected conmore just than those of his predecessors, and if he did not cerning the structure and functions of plants : to these he avoid the error of supposing certain plants to be mere abor- added an exposition of what he considered the philosophy tions of more perfect species, as many grasses of corn, he of classification, as indicated partly by human reason, and amply redeemed his fame by the correction of other mis- partly by experience; and from the whole he deduced a takes. From differences in the fruit and the seed of plants, classification which is unquestionably the basis of that which, he formed a system which, though purely artificial, and under the name of the system of Jussieu, is every where renever much employed, had the merit of calling attention cognized at the present day. For proofs of this, we refer strongly to the existence of a class of important characters our readers to the memoir of Ray in the present work: we which had previously been either overlooked or undervalued. will only observe in this place that he separated flowering
But notwithstanding the attempts thus made by a few from flowerless plants; that he divided the former into mo. distinguished men to elevate the science to a higher sta- nocotyledons and dicotyledons, and that under these three tion, and to reduce it to soine general principles, it still con heads he arranged a considerable number of groups, partly tinued to languish and to remain for the most part in the his own, partly taken from Lobel and others; which are hands of the most ignorant pretenders, and in no country substantially the same as what are received by botanists of more so than in England. We find, upon the authority of the present day under the name of natural orders. It is the celebrated Ray, that in this country in the middle of singular enough that the merits of this arrangement of the seventeenth century it was in the most lamentable state. John Ray should have been so little appreciated by his At that time the standard book of English botanists was a contemporaries and immediate successors, as to have been publication called Gerarde's · Herbal,' which was, as Ray tells but little adopted ; and that, instead of endeavouring to corus, the production of a man almost entirely ignorant of the rect its errors and to remove its imperfections, botanists learned languages, in which nevertheless all books on science occupied themselves for several succeeding years in attempts were at that time written. The principal part of the work at discovering other systems, the greater part of which were was pirated from the ‘Pemptades of Dodoens, turned into abandoned almost as soon as they were made known. English by one Priest, and, in order to conceal the plunder, Rivinus, Magnol, Tournefort, and Linnæus were the most the arrangement of Dodoens was exchanged for that of celebrated of these writers; but the two last alone have had Lobel, while the whole was made up with the wood-blocks any permanent reputation. Tournefort, who for a long time of Tabernæmontanus' Kräuterbuch, often unskilfully trans stood at the head of the French school of botany, proposed, posed and confounded. At last a change, as sudden as it in 1694, a method of arrangement, in its principles entirely was important, was produced in the science by the applica- artificial, but which in some cases was accidentally in action of the microscope to botanical purposes.
cordance with natural affinities. It was founded chiefly The Third Æra.--About the middle of the seventeenth upon differences in the corolla, without the slightest recentury this instrument was first employed in the examina- ference to physiological peculiarities; and is now forgotten, tion of the elementary organs of plants, about which no except in consequence of its having furnished some useful thing had been previously learned since the time of Theo- ideas to Jussieu, as will be hereafter shown. phrastus. The discovery of spiral vessels by Henshaw in The Fifth Æra.-Linnæus was a genius of a different and 1661, the examination of the cellular tissue by Hook at a a higher order. Educated in the severe school of adversity, somewhat later date, at once excited the attention of ob- accustomed from his earliest youth to estimate higher than servers, and led at nearly the same time to the appearance all other things verbal accuracy and a logical precision, of two works upon vegetable anatomy, which at once so which are often most seductive when least applicable; ennearly exhausted the subject, that it can scarcely be said to dowed by nature with a most brilliant understanding, and have again advanced till the beginning of the present cen- capable, from constitutional strength, of any fatigue either tury. Grew and Malpighi, the writers thus adverted to, of mind or body, this extraordinary man was destined to but more especially the former, combined with rare powers produce a revolution in botany, among other branches of of observation a degree of patience which few men have ever natural history, which in some respects advanced and in possessed. They each examined the anatomy of vegetation others retarded its progress far more than the acts of any in its minutest details, the former principally in the abstract, one who had preceded him. He found the phraseology bad, the latter more comparatively with the animal kingdom. and he improved it; the nomenclature was awkward and inVarious forms of cellular tissue, inter-cellular passages, spi-convenient, he simplified it ; the distinctions of genera and ral vessels, woody tubes, ducts, the nature of hairs, the true species, however much the former had been improved by structure of wood, were made at once familiar to the bo. Tournefort, were vague and too often empirical; he defined tanist; the real nature of sexes in plants was demonstrated; them with an apparent rigour, which the world thought ad. and it is quite surprising to look back on those days from mirable, but which Nature spurned; he found the classificathe present high ground on which botany has taken its tions of his day so vague and uncertain, that no two persons stand, and to see how little the views of Grow at least have were agreed as to their value, and for them he substituted a
scheme of the most specious aspect, in which all things superficial botanists; of men who supposed that nomenseemed as clearly circumscribed by rule and line as the clature and verbal criticism constitute the whole objects of fields in the map of an estate ; he fancied he had gained the science; who have been distinguished more for their the mastery over nature, that he had discovered a mighty total neglect of everything beyond mere technicalities, than spell that would bind her down to be dissected and anato- the old botanists for their disregard of the latter; who have mized, and the world believed him; in short, he seized upon had no general views, and apparently no power of applying all the wardrobe of creation, and his followers never doubted their means to any intelligible end, and who, consequently, that the bodiless puppets which he set in action were really in the countries where they have flourished, have so far the divine soul and essence of the organic world. Such was lessened the science in public estimation, and done as much Linnæus; the mighty spirit of his day. Let us do this great to retard its progress as Linnæus did to advance it. man that justice which exaggeration on the one hand, and The maxims however of Ray, and the great general views detraction on the other, have too often refused to him; and of that illustrious naturalist, were destined not to fade even let us view his character soberly and without prejudice. We before the meteoric brilliancy that surrounded the throne of shall then admit that no naturalist has ever been his supe- Linnæus. French botanist, Antoine Laurent de Jussieu, rior ; and that he richly merited that high station in science soon entered the field to oppose the latter. In the year 1789, which he held for so many years. His verbal accuracy, just eleven years after the death of Linnæus, he produced, upon which his fame greatly depends, together with the re
under the name of Genera Plantarum,' an arrangement markable terseness of his technical language, reduceil the of plants according to their natural relations, in which crude matter that was stored up in the folios of his predeces- the principles of the great English botanist are tacitly adsors into a form that was accessible to all men. He sepa- mitted, and his fundamental divisions adopted in combirated with singular skill the important from the unimportant nation in part with those of Tournefort, and in part with what in their descriptions. He arrayed their endless synonyms are peculiar to the author himself
. Jussieu possessed in a with a patience and lucid order that were quite inimitable. happier degree than any man that has succeeded him the By requiring all species to be capable of a rigorous defini- art of adapting the simplicity and accuracy of the language tion not exceeding twelve words, he purified botany of the of Linnæus to the exigencies of science, without encumberendless varieties of the gardeners and herbalists ; by apply- / ing himself with its pedantry. He knew the impossibility ing the same strict principles to genera, and reducing every of employing any single characters to distinguish objects character to its differential terms, he got rid of all the cum so variable in their nature as plants; and he clearly saw to brous descriptions of the old writers. Finally, by the inven- what evils all artificial systems must of necessity give rise. tion of an artificial system, every division of which was de- Without pretending then to the conciseness of Linnæus in fined in the most rigorous manner, he was able so to classify forming his generic characters, he rendered them as brief as all the materials thus purified and simplified, that it seemed was consistent with clearness; without peremptorily excludas if every one could become a botanist without more pre- ing all distinctions not derived from the fructification, vious study than would be required to learn how to discover he nevertheless made the latter the essential considerwords in a dictionary. Add to all this, the liveliness of his ation; instead of defining his classes and orders by a few imagination, the skill with which he applied his botanical artificial marks, he formed them from a view of all knowledge to practical objects, and the ingenuity he showed the most essential parts of structure; and thus he colin turning to the purposes of his classification the newly- lected under the same divisions all those plants which are discovered sexes of plants, and we shall at once comprehend most nearly allied to each other. Hence while a knowledge what it was that exalted Linnæus so far above his contem- of one plant does not by any means !ead to that of another poraries. But great as the impulse undoubtedly was which in the system of Linnæus, it leads directly to the knowledge Linnæus gave to botany, there were vices in his principles of many more in the classification of Jussieu ; which has
ch, although overlooked during his life, have subse- accordingly gained the name of the natural system. This quently been productive of infinite evil. There is no such at once brought the science back to a healthy state; it thing as a rigorous definition in natural history ; this fact demonstrated the possibility of reducing the characters of Ray had demonstrated to arise out of the very nature of natural groups to words, contrary to the opinion of Linnæus, things ; and consequently the short phrases by which spe- who found that task altogether beyond his powers ; it did cies and genera were characterized by Linnæus were found away with the necessity of artificial arrangements, and equally applicable to many other plants besides those for giving a death-blow to verbal botany, it laid the foundation which they were intended : hence arose a new source of con- of that beautiful but still imperfect superstructure, which fusion, inferior only to that which it was intended to correct. has been erected by the labours of Brown, De Candolle, Differential characters, which would be invaluable if we had and others. If the system of Jussieu were not a return all nature before us, were found in practice to lead to inces- to that of Ray, modified only and improved by modern dissant errors, so soon as some new species was introduced into coveries, we should certainly have taken this period for the the calculation : they also laboured under the great fault commencement of of conveying no idea whatever of the general nature of the The sixth and latest æra in our science. But it was plants to which they related : thus the Portuguese botanist reserved for a man whose fame lies chiefly in the literary Loureiro, who attempted to determine the plants of China world to effect the last great revolution that the ideas of by the systematic writings of Linnæus fell into the singular botanists have undergone. In 1790, one year after the error that the hydrangea was a primrose. With regard to appearance of Jussieu's Genera Plantarum, the German poet his artificial system of classification, it was found that it Göthe published a pamphlet called “The Metamorphosis looked better in the closet than in the field; that the neat- of Plants.' At that time the various organs of which ness and accuracy of the distinctions upon which it was di. | plants consist had been pretty well ascertained, the disvided into groups existed only upon paper, and that excep- tinctions between the leaf, the calyx, the corolla, the tions without end encumbered it at every turn. This, which stamens, and the pistil, were in a great measure understood, is perhaps inseparable from all systematic arrangements, and the botanists were not a few who fancied there was would not have been felt as so great an evil, if there had nothing more to learn about them. Nevertheless even been any secondary characters by which the primary ones in the time of Theophrastus a notion had existed that could be checked, or if the system had really led with all its certain forms of leaves were mere modifications of others difficulties to a knowledge of things. But it was impossible that appeared very different, as the angular leaves in not to perceive that it led in reality to little more than a croton of the round cotyledons or seminal leaves of that knowledge of names, and that it could be looked upon as plant. Linnæus himself had entertained the opinion that nothing beyond an index of genera and species. Let us all the parts of a flower are mere modifications of leaves repeat, however, that these objections were of little weight whose period of development is anticipated (prolepsis planin the time of Linnæus ; the force of many of them was tarum); Ludwig in 1757, and more especially Wolff in hardly felt, when scarcely a twelfth part of the species now 1768, had stated in express terms that all the organs of known to exist was upon record; and the world was natu- plants are reducible to the axis and its appendages, of the rally inclined to embrace with ardour the clearness and pre- latter of which the leaf is to be taken as the universal type. cision of the Linnean language, notwithstanding all its But the theory of Linnæus was anciful; Ludwig was a faults, in exchange for the cumbrous, vague, or unmethod writer of too little authority in his day to succeed in estaical descriptions of those who preceded it. The great blishing a doctrine so much at variance with received evil that has arisen out of the system of Linnæus has been opinions; and the theory of Wolff was propounded in a this : that it has led to the formation of a large school of paper upon the formation of the intestines in animals, which
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