Cyathea glauca, an arboreous fern.

(6.) Let not the bearing of this statement, however, by any one, be misunderstood! Remember, it is not science which makes the difficulty she here points out: she only shews what already is; just as a microscope does not make the hairs on a mite's back, but only brings them within our sphere of vision.

(7.) Examine for a moment some few specimens illustrative of the different departments of the vegetable world; such as mushrooms [vide § 57], flags [vide 41, 47, 51], and mosses [vide § 59]; jointless

and jointed ferns [vide § 64]; grasses [vide § 72], sedges, rushes, lilies [vide§ 75]; palms [vide § 81], pines [vide § 85], cycases [vide85], and forest trees [vide § 97, 100], or other more showy herbs, and shrubs, and selworts [vide § 111]; of each of which extensive sections, examples, however copious, must of necessity be comparatively meagre, and yet which are scattered in such infinite profusion "o'er all the deep green earth," that their varied forms and beautiful appearances are familiar to the least observant. Let the inquirer examine these, and say whether they do not confirm the dogma of him of old, that a vegetable is a various, a very various thing, of which it is difficult to give a definition; and whether they do not equally proclaim that science does not make the difficulty she here points out; whether they do not declare that she only shows what already is, although it may have hitherto escaped our observation.

The perception of difficulties does not increase, neither does ignorance thereof lessen their extent. The unlearned do not know more truly because they are insensible of the imperfections of their knowledge, any more than a road becomes smooth to the purblind, merely because they do not see its roughness. What

ever is, still is, whether men know it or know it not.

Doubtless,

from the beginning eight planets always were, although the ancients knew but seven; for Herschel's telescope did not create the Georgium Sidus, but only showed to man what mortal eyes had never seen before.

(8.) But the difficulty of diagnosis between animals and plants, and even between living and lifeless beings, so often and by so many dwelt on, is rather a speculative than a practical obscurity. Every one is sensible of differences existing between the numerous productions of nature; for, were not such differences obvious, the whole would be esteemed not various, but the same. All persons, then, distinguish the peculiarities that mark the successive grades of physical existence, though few are competent to state precisely in what that difference consists. The one is the unsought observation of the savage, the other the hard-earned achievement of the sage; the former a perception that no one can avoid, the latter a science in which, not seldom, the wisest are at fault.

(9.) Now this great and extraordinary variety, this almost infinite diversity, in the structure and functions, the characters and appearances, the properties and purposes of plants, which renders it so difficult to frame a concise definition, rigidly including the whole, and as strictly excluding all that we think not plants, which circumstance so many have bewailed, and which some superficial philosophers have regarded as the reproach of botany, because it suits not their weak and artificial systems of arrangement, so far from being an "opprobrium botanicum," is, in truth, one of the chief advantages of which the science has to boast; so that, if we wished for a change at all, we should wish, although it is needless, that the variety were ten times greater.

(10.) Because, although the vegetable kingdom, by stretching to such wide extremes, may render the absolute definition of a plant somewhat abstruse and difficult; and although in some cases, at the confines of the animal and vegetable reigns, doubts may arise as to whether certain microscopic beings are animals or plants; belong to this kingdom or to that, or, in fact, to either, still their ambiguity, which has been lamented as an extreme disadvantage, when rightly viewed, becomes a guide, as it at once affords an index to elucidate the things themselves; for their very obscurity indicates their station, by referring them to the debateable land of natural existence. And, furthermore, it of course will follow that

the greater the differences existing among decided plants, the stronger will the contrasts be, and, of course, the more readily will they be distinguished from each other: a secondary advantage, which, in practice, far outweighs any slight inconvenience attending the diffuseness of the primary definition.

(11.) Still when, as botanists, we presume to talk of plants, it may fairly be required that we should attempt to solve the question that so continually recurs: viz. what is a vegetable? For plants are the principles upon which all botanic lore depends; they are the very subject matter upon which we must discourse: and as, although we cannot absolutely, we can relatively define them, this relative definition should be given; and the more so as it will, in truth, be found to be all that can legitimately be sought, in any department of natural philosophy.

(12.) With this relative definition we shall therefore rest content; for the search after the abstract and the absolute too often becomes, as Butler well observed, on a somewhat similar occasion,

"An ignis fatuus that bewitches,

And leads men into pools and ditches."

(13.) To show what constitutes this various thing we call a vegetable; i. e. to indicate the various phenomena exhibited by certain physical existences, to note what characters distinguish the organic from the inorganic world, and amongst organic beings the vegetable, or merely vital, from the animal or sensual creation; in a word, which constitute the several grades of men, of brutes, and of plants, is doubtless a worthy task; and, as the pursuit involves much useful and important knowledge, it must form a part of every enlightened botanist's researches. It is the time, and mode of investigation, that admit dispute; not the necessity of the research itself.

(14.) Plants are very numerous, and often very various; but the relative similitudes and comparative differences by which they are associated and distributed into more or less comprehensive groups, and allied to or distinguished from each other, as well as to and from the contingent animal and mineral kingdoms, even when great, can be duly appreciated, and when slight, can often be perceived, only by those who are conversant with their positive characteristics; i. e. are practically familiar with the subjects to be distinguished and defined. Hence, as plants are the subjects

of inquiry, a practical demonstration of their positive individual characters would seem rightly to precede a collective theoretical definition of the vegetable reign, and its comparative demarcation and extent; and such is the plan we here design, in the first place, to follow.

(15.) For the present, therefore, we shall let the more speculative problem pass; to it, however, we shall return hereafter: and its consideration is only now delayed, that a previous practical demonstration of plants, as they are found in nature, may the better enable us to venture on its solution. Hence, to a not distant future we postpone the definition of a plant, and now propose, as a more useful preliminary step, to practically show what a varied thing a vegetable is.

(16.) Plants are the subjects of botany; their attributes the objects of the science: hence, two schemes of study, the subjective and the objective, lie before us; each of which may be pursued in opposite courses; i. e. either by analysis or synthesis, whence the anterior and posterior arguments result; between these the selection must be made. The former descends from generals to particulars, the latter ascends from effects to causes; that being essentially more abstract, this more practical, in its course. Each has advantages peculiarly its own; hence, both should in turn be studied, and neither exclusively neglected or pursued. But, as the anterior argument requires much antecedent knowledge, while the posterior can trace back from none, that being the fruits of learning, while this is the means to learn; although the first is the most comprehensive, the last is the most familiar, and hence it is that with which we shall commence our labours.

(17.) Although differing essentially from the usual schemes. of investigation, synthesis shall here precede analysis, and the subjective now be made the forerunner of the objective view; for it seems advisable, at least occasionally, to commence with a practical demonstration of plants as they are found to exist in nature; and to show their positive characters before comparisons are instituted between them and the other kingdoms of the organic and inorganic worlds: in fact, first to have materials to compare before comparative views are taken. Hence, after giving a general conspective glance at the whole, it is proposed to demonstrate the

special structures, functions, properties, and uses of each succeeding group of plants, from the lowest to the highest grades; and this before any general views or comparisons are instituted, even between the varied developments of equivalent organs, as pervading the whole vegetable kingdom, and much before any are made between the different, and often essentially diverse, constitutions of the adjacent animal and inorganic reigns.

(18.) It is evident that the subjective synthesis will demand much less previous knowledge, and require much less to be assumed, than any other mode of investigation. Still, even here, something must be accorded: we must grant what, however, few would venture to deny, for it is a postulate without which no step can be advanced; viz. that the examples adduced, and to which reference has been made, as the flags, funguses, and mosses, ferns, grasses, and so forth, are truly vegetables. These groups have been selected merely to illustrate the varied characters of plants: that they are really such, must be proved hereafter; that they are what they are described, must be granted now.

(19.) Something must be assumed in every science; and, to profit by the experience, the pupil must be content to take something at first on the authority of the teacher; seldom, however, more than admits of no dispute. For, although it is convenient, in order that every point, even the simplest, may receive its due share of consideration, to assume, and, as far as possible, to act on the assumption, that all students are totally ignorant of the subjects to be discussed, yet it is notorious that such tabulæ rasæ are never met with: many things are unavoidably known to almost all; our very existence convinces us of many: such, therefore, as such alone should be, are the postulates assumed; and, from the certainty of things already known, we either proceed to inform ourselves respecting those which are as yet unknown; or not only this, but, from knowledge thus acquired, we are enabled to correct those errors by which, either from ignorance or prejudice, we had been previously enthralled.

(20.) The following simple enunciation of some of the chief results of the analytic scheme, viz. the segregation of acknowledged plants to constitute the vegetable kingdom, and the subordinate distribution of this kingdom into secondary and tertiary groups, or classes, if used, as here proposed, merely as a guide,