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and the latter can now gain no attention, or is only adverted to that it may receive rebuke. In proportion to the predominance of the method now in vogue over that of Aristotle and the middle ages, has been the rapid advance of our scientific knowledge, our acquaintance with the operations of nature, and the more intimate and secret workings by which she accomplishes her great results. Take for instance the various branches of chemistry and physiology, in which the modern philosopher, as though a spirit of a superior order, becomes cognizant of forces and effects, which, though acting and resulting equally as now, from the first period of the present constitution of our planet, have been hitherto unobserved and unsuspected; examines the most minute and intimate structure of organized beings, explaining many of the more secret operations of vitality to which these subserve; or traces the almost imperceptible gradations of development ascending through innumerable species, from the lowest organization to himself, in whom, so far as regards the inhabitants of this planet; the series reaches its highest limit

. The work before us ably illustrates the progress that had been made in the various branches of our botanical knowledge up to the present time; though, perhaps, with regard to this department of natural history, the contrast between the past and the present is somewhat less striking and complete than in the instance of chemistry or animal physiology. The objects of which the science of Botany treats are amongst the most familiar and attractive which present themselves to our attention, as well as amongst the most important for the sustenance and convenience of our race. Hence, from the earliest period, the peculiarities of form and structure, as well as of the habits and properties of plants, have been matter for careful observation and research. Mankind seems very soon to have found the advantage of forming, some arrangement of the various plants which fell under their observation, or ministered to their convenience, togetber with descriptions by which the different species might be recognised and discriminated. Such attempts towards the science of botany are apparent from the times when history commences:—we read in the earliest writings of grass, -and herb yielding seed,—and fruit tree yielding fruit;' we are told that Solomon spake of trees, from the cedar tree that is in Lebanon, even unto the hyssop that springeth out of the wall;' Theophrastus had his water plants and parasites, pot-herbs, and forest-trees, and corn plants; Dioscorides had aromatics and gum-bearing plants, eatable vegetables, and corn herbs. The progress of botanical knowledge is somewhat less marked likewise, inasmuch as the structure and the phenomena of vegetable beings are less complex and subtle than those which are disclosed by researches in other branches of natural science. The triumphs of an original observer in the science of botany are hence less striking and conspicuous than are those of a Davy, or a Faraday, of an Harvey, a Hunter, or a Cuvier. And, again, although the true and independent philosopher can allow little force to the captious inquiry of cui bono? so often objected to his labours by shortsighted Utilitarians; yet it may not be denied that the greater importance of the practical results which have followed investigations in the other departments which we have instanced, are further inducements likely to secure for them a succession of zealous workers more numerous than those who devote their powers to search into the phenomena of vegetable life. Only the more meritorious then (unstimulated by these secondary motives,) must be the labours of such men as Linnæus, Ray, Jussieu, Brongniart, Brown, De Candolle, Greville, Mirbel, Hooker, Lindley, and others, who have advanced Botany from the occupation of a herbalist to the scientific elevation which it now holds.

In attempting some illustration of the most recent of the works of the last mentioned botanist, we must remark, in the first place, that the study of botany, like that of other branches of natural history, comprehends two principal divisions; the one having relation to vegetable structure and functions; the other to the description of species, and their classification upon some definite and appropriate system.

These two divisions may be taught, or the study of both may be pursued, contemporaneously; but as the former is necessary for the elucidation of the latter, it is impossible that systematic botany can be either taught or studied to any really scientific or useful purpose, unconnected with the facts of anatomy and physiology, upon which alone can be founded a practically useful system, one of the chief purposes of which, indeed, is that it may reciprocally serve for the further illustration of such facts as those upon which it is itself founded.

He is not a botanist, in any worthy signification of the term, whose knowledge is equal only to the distinguishing of different species of plants by their external appearance, and applying to them their technical appellations, aided much, perchance, in his diagnosis, by frequent reference to engraved representations, or whose practice is limited to the arrangement of his specimens in a herbarium. Such an employment is, indeed, a harmless recreation, one in which the phrenologist might recognise the control of the organs of order and acquisitiveness; but it is too much to dignify it as a scientific pursuit.

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The work before us combines much of both the divisions of botany which we have specified as necessary to constitute the science in its integrity.

Its object is to give a concise view of the state of Systematical • Botany at the present day, to show the relation, or supposed * relation, of one group of plants to another; to explain their

; geographical distribution, and to point out the various uses to • which the species are applied in different countries.'

The systematic arrangement adopted is not merely stated, but is illustrated throughout by explanations of the structural and physiological peculiarities in which are to be traced the natural affinities of the different orders. A work fulfilling these intentions differs entirely from a · Flora,' or mere classical catalogue of plants, characterised merely by the most brief descriptions which can suffice for their recognition; and must necessarily combine a great amount of information in every department of the science of which it treats.

We have spoken of the natural affinities of plants; an arrangement which has these for its foundation is called a Natural System of Botany, antithetically distinguishing it from an Artificial System; by which latter is understood any mode of classification whereby plants may be conveniently arranged with reference to some external particular easily recognised, however accidental and unimportant-facility of reference being the only object intended upon such a plan. That artificial system which has attained by far the greatest celebrity—as being the most available for those purposes which such a system is capable of subserving—is the sexual system, as it is called, of Linnæus, which determines the classes of plants according to the number and position of the stamens, and the orders by the numbers of the styles or stigmata contained in their flowers. These particulars are so easily recognised, and generally so invariable in each species, as to be peculiarly available for the purposes of an artificial classification; so that, among such systems, this one has long been recognised as the facile princeps. The objection is, that by thus confining the attention to a single peculiarity of structure, to the exclusion of all others, though of equal or even of higher importance, orders and genera the most dissimilar are often closely approximated, and those placed far apart which are most nearly allied. Thus, plants so intimately related as are sage and marjorum, for example, are separated by one-half the entire system; and even the grasses are not all in the same class; whilst, on the other hand, genera so different as Euphorbia and Carex are associated together. Linnæus himself saw clearly the insufficiency of any merely artificial plan, and attempted likewise


a natural system, which he declared to be, ' Primum et ultimum in botanicis desideratum.'

Twenty years ago, however, this artificial system of Linnæus was the one universally adopted by botanists in this country; now, this once popular system is declared by our author to be a 'matter of history merely;' and the merit of the substitution of a more scientific arrangement, upon a natural system, in this country, is claimed with justice by Dr. Lindley as belonging to himself.

The natural system, which has displaced the one of which we have spoken, is described as being that which is founded on the principle that all points of resemblance between the various

parts, properties, and qualities of plants shall be taken into consideration; that thence an arrangement shall be deduced in

which plants must be placed next to each other, which have the greatest degree of similarity in those respects.'

The advantages of this system over the other are of a decidedly practical nature, and not merely theoretical or scientific. Upon this plan, a knowledge of the properties of one plant enables the botanist to judge scientifically of the qualities of other plants

naturally allied to it; so that the physician, acquainted with 'the natural system of botany, may direct his inquiries when on

foreign stations, not empirically, but on fixed principles, into 'the qualities of the medicinal plants which have been pro* vided in every region for the alleviation of the maladies pecu* liar to it.' Though Dr. Lindley has thus chosen his illustration of the practical utility of this system from the advantages which it may afford to the more enterprising members of the medical profession, yet, obviously, it is capable of much more general application; the poisonous nature of an unknown species, or its harmless and nutritious properties, may, by this method, be at once declared to the scientific colonist or the traveller, as well as its probable value for any of the economic purposes to which civilization applies the varied productions of the vegetable kingdom. With respect to its scientific value, we before alluded to the help which this system gives to the farther illustration of the real structure or function of parts which may otherwise seem anomalous or unintelligible; by comparing a plant which may present such difficulties, in any of its parts, with other plants, between which and itself close affinities do evidently exist, the true analogies of the questionable organ may often at once declare themselves. Again, by forming an arrangement of the entire known vegetable kingdom in genera, orders, and classes, according to the natural affinities and true relations of their species with each other, we are conscious of a new pleasure in acquiring clearer and more enlarged views of the connexion which exists throughout the organic world, and of the harmony which pervades the works of nature; we see how almost insensible are the gradations of development between the lowest and most insignificant instance of vegetable life, and its most noble representatives-between the green slime upon a moist pavement and the majestic timber trees of the forest; and we no longer regard each specific form as an isolated fact, but as forming an integral part of one comprehensive and well-ordered scheme, embracing the varied works of nature throughout the most distant countries and the most opposite climates.

At the present day, when the research of botanists has made us acquainted with such numerous and diversified forms of vegetation in all parts of our globe, so that upwards of 80,000 existing species are at present known and described; and when not merely recent plants are brought under observation, but the fossil remains of species which have passed away for ages, are disentombed from their long burial in the strata, and exactly classified,--the difficulties which present themselves in the exposition of such a scheme are very different from those which would have occurred at an earlier period, when our acquaintance with species was much more limited and less exact. Then the formation of such an arrangement in regular progression, and the subdivision of the whole into definite groups, would appear a work of no doubtful practicability, the true principles being once established, and only to require a more extensive knowledge of species for its complete accomplishment. The groups thus formed would many of them appear distinctly limited, though not, perhaps, advancing always with a uniform progression; gaps, or intervals here and there presenting themselves, the occupants for which, it would be fair to conclude, a more extended knowledge would subsequently supply. Now, this increase of knowledge is obtained with more than anticipated profusion, but the systematist does not find his difficulties removed, only their nature is somewhat altered; the negative of deficiency has passed the equilibrium, and has reacted into as embarrassing an excess.

It is true that many a hiatus has been appropriately filled up; but at the same time, the distinct limits between many of the groups have gradually disappeared, and the regular progression from forms of lower to those of higher development now appears diverted by many a flexure and ramification from a direct

If we consider only the primary colours in the solar spectrum, the red, the yellow, and the blue are clearly distinct; but a nicer observation shows the intermediate tints by which


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