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the history of the Jews and Carthaginians, we might have said all, and neither made an exception of the Royal Botanist, who treated of all plants, from the lofty cedar which adorns Lebanon, down to the diminutive vegetables which disfigure walls ; nor of the Carthaginian Mago, who wrote twentyeight books de re Rustica, which were thought worthy of being transferred to Rome, among the other valuable 'spoils of Carthage, and were translated from the Punic into the Latin language, by order of the Senate.

While the number of ascertained useful vegetables was small, those to whom they were known would point them out to their disciples, who, in that way, would become acquainted with their general appearances, and other sensible properties : But, when accidental discoveries, quackery, and intercourse between neighbouring nations, had augmented their number considerably, the necessity of accurate descriptions would become apparent.

Among the Greeks, though herbs were employed as medicines long before the Trojan war, and Cadmus had furnished the means of conveying their discoveries to posterity, yet many centuries elapsed before any writer appeared, who deserved the name of a botanist. Theophrastus the favourite disciple of Aristotle, who succeeded him in the direction of the Peripatetic school, and inherited his library, is the first author whose works have reached us, who obtained that appellation. Pythagoras, Hyppocrates, Cratejas, Aristotle, and many others, had treated indeed of vegetables before him ; but their writings are either partly, or entirely lost, or contain but little of importance.

of the ten books which Theophrastus wrote on botany, nine have been preserved, containing an account of more than 500 vegetables, which he divides into trees, shrubs, and herbs, a very humble attempt at methodical arrangement; yet, singular as it may appear, this clumsy distribution of vegetables prevailed, even "among botanists, from his time, till near the end of the 17th

century, and for some time cramped the first efforts made towards establishing a more perfect arrangement. His descriptions, as was indeed to be expected, are still more imperfect than his arrangement; for much more attention is required to detect those distinguishing marks by which closely allied genera or species are to be discriminated, than to trace general resemblances. Had he been aware, that all the trouble he had taken to point out the uses of the vegetables of which he treated, would have been lost for want of such descriptions as might enable his readers to recognize them, he probably would have bestowed more pains on that subject, and botany might have received more early improvement..

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The same inaccuracy of description, and want of method, in atranging vegetables, pervaded the writings of all the ancient botanical authors, and rendered their works obscure, and frequently unintelligible. In reality, little or no addition was made to botanical knowledge by any of them, except in the number of plants they mention, from the time of Theophrastus, till some time after the revival of learning in Europe, a period of nearly 2000 years.

· Dioscorides, who lived about the time when the Roman empire had nearly arrived at its greatest extent, mentions about 700 plants, which he divides as articles of materia medica, into arom matic, alimentary, medicinal, and vinous. That industrious compiler, Caius Plinius Secundus, whose ardent curiosity cost him so dear, in his Historia Mundi, 15 books of which are occupied with botanical and agricultural matters, mentions above 1000 plants, which he divides, according to the ancient arrangement, into trees, shrubs, and herbs. Neither this author, however, nor any of his contemperaries, seem to have considered botany as a branch of natural history, but merely as an account of useful vegetables; for he says, there are many more plants than those he has mentioned, which grow by the road sides, in hedges, and in the fields, which are of no use, and therefore have no names. All the succeeding authors who wrote on this subject, both European and Arabian, till about the beginning of the 16th century, were employed in copying their predecessors, and in making commentaries on their writings: at last, however, some, tired of studying the ancients, began to study nature; and, convinced of the necessity of methodical arrangement, made several inefa fectual attempts to arrange the plants they had collected, by means of their leaves, stems, and roots. Conrad Gesner, a native of Zurich, about the middle of the 16th century, first suggested the propriety of arranging vegetables, by means of their. flowers and fruit, but formed no system of his own. In 1582, Andrew Cæsalpinus, a Florentine physician, and professor of botany at Padua, published an arrangement of vegetables, according to the principles proposed by Gesner, of which, as the first that had appeared in Europe in any way deserving the name of systematic, some little account may be interesting.--He arranged all vegetables into fifteen classes, as follows.

ARBO

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ARBORES. Arbores, corculo ex apice seminis • - - .. . - 1 - bafi seminis - - - - - - 2

HERBÆ.
Seminibus folitariis .

| Pericarpiis folitariis unilocularibuscarnofis,
| Simplici, e { bacca vel pomo - - .

Pericarpiis folitariis unilocularibus ficcis
l membranaceis - . . . s

Seminibus duobus nudis
Duplici, e Pericarpiis bilocularibus, vel duobus se.

1 minum receptaculis . .

s Pericarpiis trilocularibus vel feminibus triFructu, Triplici, e 3 bus nudis, radice non bulbofa - 8

(Pericarpiis trilocularibus, radice bulbosa 9 1 Quadruplici, e Seminibus .

- Seminibus pluribus intra calycem comI munem, petalo ad femen fingulum u

· nico . - - - 11 & 12 Seminibus pluribus nudis, corolla feminiI bus communi

( Pericarpiis pluribus vel multifarium divifis 14 Nullo visibili ,•

- - - - These he again subdivided into 47 subdivisions.

Two circumstances render this method imperfect, and prevented its general adoption. First, the marks of the classes are taken almost exclusively from the fruit; secondly, the ancient division is in great part retained, though a consciousness of its defects, had led the author in so far to disregard the authority of Aristotle and Theophrastus, as to attempt to improve it by classifying his vegetables under two divisions only ; shrubs being left out altogether as a division.

After the lapse of a century, Dr Morison, a native of Aberdeen, and professor of botany at Oxford, by employing the parts of the flower and the general habit of the plant, in addition to those of the fruit, endeavoured to improve the method of Cæsalpinus, which had lain neglected ever since the death of its author. Morison also attempted to correct the defects of the ancient division, by dividing all vegetables into ligneous, and notligneous. The ligneous he formed into three classes, trees, shrubs, and undershrubs : the not-ligneous, i. e. herbs or grasses, into fifteen. The subdivisions of which amount to one hundred and eight. · In 1682, John Ray, a native of Essex, who has acquired celebrity in other branches of natural history, published a methodical

arrangement

arrangement of vegetables, founded on that of Cæsalpinus and Morison, consisting of twenty-five classes, which he afterwards improved and republished in 1700. His improved method consisted of thirty-three classes, which is divided into two grand die visions, viz. plants destitute of buds, i; e. herbs; and plants producing buds, i. e. trees. Herman, professor of botany at Leyden, Christopher Knaut, the celebrated Boerhaave, and many others, formed systems, by altering and attempting to improve those of their predecessors.

When any set of objects is too numerous to be comprehended by the mind at once, they may, by means of marks of distinction or resemblance, be divided or united into smaller assemblages, which (if the analytic method be followed) may be again divided into subdivisions, or orders; these again into genera, and genera into species : or, if the synthetic method be adopted, species may be assembled into genera, &c.

There are two ways of accomplishing this; the one, by uniting into the same assemblage, such species aś, from an agreement in several particulars, seem to be connected by a close affinity established by nature; the other, by forming into arbitrary associations a number of species which happen to agree in some accidental circumstances. The former is called natural, the latter artificial method. All the authors of systems we have hitherto mentioned, adopted the natural method. In the vegetable kingdom, it frequently happens, that a great number of species agree in so many particulars, as evidently to demonstrate them to be members of the same natural family. Among the grasses, for instance, the family resemblance, the similarity in the form of the leaves, in the construction of the stalks, in the parts which compose the flower, and in the nature of the seeds, is so great in all of them, as easily to enable any one who may be acquainted with only one or two species, to recognize any other almost at first sight. There are other tribes of vegetables, the different species of which may be recognized with equal facility, even by those who have but a slight acquaintance with them; but this is by no means the case with all. Though nature generally exhi. bits a wonderful degreee of regularity, she frequently makes considerable deviations; and anomalous productions are to be found, which, though they possess the principal features of one family, yet, in some particulars, so far resemble another very distinct tribe, as to make it doubtful to which of the two they ought to be referred, without a minute investigation by one well acquainted with the distinguishing characters of both. Nearly allied families, likewise, frequently run into one another so imperceptibly, as to render it no easy task to draw the line of separation.

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For these reasons, it is frequently difficult to define natural families, in such a manner as to comprehend all their irregular members, without at the same time leaving room for the admission of species which do not belong to them.

Whatever may be said, therefore, in favour of natural classes, and however fit they may be, for the use of those who are well acquainted with botany, at a time when the greater part of the vegetables this globe produces, shall have been discovered and described ; while they are deficient in point of facility, they cannot be the most proper for beginners, nor could they be so even for botanists themselves, at a period when, comparatively, few plants were known.

A. Quirinus Rivinus, professor of botany at Leipsic, perceive ing the defects of the natural systems proposed by his predecese sors, endeavoured to form an artificial one, founded on the regu. larity and irregularity of the corolla, and on the number of the petals of which it was composed, which he published in 1690. It consisted of the eighteen following classes.

Monopetali.
Dipetali.

Tripetali.
s Regulares, Tetrapetali.'

Pentapetali.

Hexapetali.
s Perfe&i Simplices,

(Polypetali.
s Monopetali.
Dipetali.

Tripetali.
| Irregulares, Tetrapetali.

Pentapetali.
Hexapetali.
| Polypetali.

Regularibus.
I l Compofiti ex flofculis, Irregularibus.

(Re. et irregularibus. | Imperfe&ti,

Imperfectio This author was the first who ventured to disregard the stamp of antiquity, and rejected entirely the ancient division, which had so long fettered all former framers of systems.

His design was good; but he was unfortunate in the choice of the part of the flower he fixed on for the foundation of his

classes, as flowers are more liable to vary in the number of their · petals, than in any other particular: he was however more successful in the selection of the fruit for the foundation of his

orders,

Plantarum flores sunt,

vel

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