Is that science which arranges, distinguishes, and names all plants and vegetables, to enable us to study their properties and uses.

Vegetables consist of an innumerable succession of individuals which it is impossible to examine, and would be useless if it were possible. It is therefore necessary to diminish the labour by forming them into groups or classes, that the same name may apply to a great number of individuals. Now certain individual plants have so close a resemblance to others in their flower, fruit, leaves, and general appearance, that almost every man at first sight would give them the same name. Thus every man who has seen the common daisy once, and knows its name, will probably apply the same name without mistake to every other individual of the same species. This forms the first step in botany, or what is called arranging and naming plants according to their species. Nor is it only the first, but the easiest step in botany. It is also the most important; for all the individuals of the same species must in similar circumstances possess the same qualities. For example, we have no reason to doubt that each individual plant of common hemlock, or of foxglove, possesses the same medical qualities, though from their place of growth these qualities may differ in degree. It is therefore the individuals of the species alone that are useful; and the whole value of any arrangement consists in enabling the botanist to distinguish and name the individuals, with the greatest ease and accuracy. If the number of species were small, definitions or descriptions To shorten the labour, it has been found very expedient to arrange plants into various divisions; first into some very general divisions which may reduce them into a small compass, then to subdivide these general divisions into others less comprehensive, and these into others, till we arrive at the particular species which we are in search of. Thus the arrangement descends from a general division of all plants to every particular species.

Many plans of this kind have been attempted by various botanists, but the arrangement of the celebrated Linnæus is incomparably the most ingenious, most accurate, as well as the simplest and easiest. That illustrious botanist divided all plants into classes, the classes into orders, the orders into genera, and the genera into species. The orders, too, and the species, when numerous, he frequently subdivided into sections.

Objections have been made to the arrangement of Linnæus, because it admits divisions which do not appear natural. But such persons, though distinguished botanists, seem to us to have misunderstood the use and intention of that arrangement. It is not, and ought not to be, its object to give what has been called a natural arrangement; for nature does not class her productions. She places before us innumerable individuals, and leaves us to classify them according to the purpose which we have in view. If nature had formed plants into classes, orders, and genera, the botanist would have nothing to do but to study these. But in none of her works has nature done this. Classification is the work of man; and it is necessary for man merely on account of the limited nature of the faculties of his mind. Classification enables us to accomplish by several steps or operations what we cannot accomplish by one. But were our faculties much more exalted, were our penetration much more acute, and our memories perfectly retentive; could we at once survey all the qualities of objects, discern their relations to one another, and retain the remembrance of these accurately, we should have no occasion to generalize at all. As generalization or classification is necessary to aid our limited faculties, the best classification is that which leads us without error, and by the easiest process, to the particular object which we have occasion to investigate.

The arrangement of Linnæus is therefore the best: It is, however, not so perfect in some of its parts as it may yet be rendered. This is the case in some of the genera which are distinguished by marks that are too minute. But when we consider the indefatigable mind of that illustrious man, the chaos in which he found botany, and the beautiful arrangement which he gave to it, we may justly enroll the name of Linnæus in the same list with Bacon, and Newton, and Locke.

A botanical system is a dictionary by which a person who has studied the rudiments of the science may find out the name of every plant which he meets with. This dictionary has been much enlarged by the labours of the great many eminent botanists of the present time. We shall therefore point out the method of consulting it, after giving a very concise view of the principles upon which it is founded. We will give a concise view, because we think most or perhaps all the elementary books of this science tend to confound and disgust beginners by physiological definitions, and by the multiplicity of terms which they require to be studied at the very first outset. Their plan is just as if a teacher of Latin was to require his pupils first to make themselves masters of a Latin dictionary before he allowed them to translate. Our plan is to require of a beginner no more elementary knowledge than what is sufficient to enable him to consult the system as he would a dictionary. The meaning of the rest of the botanical terms we think can best be learned by having recourse to an explanation in an alphabetical form, as they occur in the investigation. This we intend to add to the present article. And we wish sincerely that every man who publishes a system of botany would do the same; for we have strong reasons to believe that different writers use the same words in different senses from one another. Linnæus, indeed, has defined his botanical terms; but in his two works, Delineatio Plantarum and Philosophia Botanica, he sometimes defines the same word differently. Now we ought to know which of his definitions succeeding botanists have adopted. Besides almost every botanist introduces terms of his own, which we shall look for in vain in the definitions of Linnæus.

ELEMENTS OF BOTANY.

The parts of a plant which it is necessary for the young botanist first to know, are the flower and fruit. These include seven; the calyx, corolla, stamen, pistil, pericarp or seed-vessel, seed, and receptacle. We will describe these in the order which will make them most easily distinguished.

1. The corolla, which in common language is called the flower, and in fruit-trees the blossom, is the part which is most beautifully coloured, which is of the finest texture, and is often odorous. It is to be found of every colour, except green, a hue which it very seldom assumes. It is white, as in the blossoms of the cherry; yellow, as in the primrose and ranunculus or butter-cup; red, as in the rose; blue, as in the violet. It is sometimes of one piece, and sometimes divided into distinct pieces, called petals. When the corolla consists of one petal, the outer or upper part, which is broad, is named the limb or border; and the lower part, which is narrow and hollow, by which it is fixed, is called the tube. When the corolla consists of more than one petal, the lower part is called a claw, and the upper lamina.

In the corolla it is necessary to attend to its form, its divisions, the number of its petals, its colour and the part to which it is attached. See Plate XCV. Fig. 11. a corolla of one petal; a, the tube; b, the laminae. Fig. 13. a corolla of more than one petal; d, the claw; b, the laminae. 2. The calyx is situated on the outside of the corolla, and enclosing it commonly at the base. It is generally of a greenish colour, and of a coarser texture than the corolla. It consists of one part, or of two, three, &c. and is then said to be one-leaved, two-leaved, three-leaved, many-leaved. The calyx is of various shapes, tubular, globular, inflated, &c.

There are seven species of calyx; perianth, involucre, glume, ament, spathe, calyptra, and volva. For explanation of these, consult the vocabulary and Plate XCV. Fig. 18, a, the calyx.

3. The pistil, or pistils, commonly appear in the centre of the corolla, from which they rise like so many columns. There are from one to twelve in the same flower, and sometimes more.

A pistil consists of three parts, the stigma, the style, and the germen. 1. The stigma is the highest part of the pistil; which is sometimes globular, sometimes cleft, sometimes cross-shaped, &c. 2. The style is the pillar or thread which supports the stigma. 3. The germen is the pedestal or base of the pistil, most commonly of a roundish or globular shape; but sometimes long and slender. Sometimes there are several germens together. See Plate XCV. fig. 12, e, the stigma; b, the style; a, the germen.

4. The stamens, which resemble threads or pillars, usually stand between the corolla and the pistil, are placed in regular order round the pistils, or alternate with the petals. They are in number on one flower from one to several hundreds. But it is not necessary to count them when they are more than twenty.

A stamen consists of two parts, the anther and the filament. 1. The anther is the summit of the stamen, containing a mealy or powdery substance called pollen, and is generally of a different colour from the filament. They are of different forms, globular, horned, &c. 2. The filaments are the threads or pillars which support the anthers. The stamens are attached to the corolla, to the calyx, to the receptacle, or to the style. See Plate XCV. fig. 18. Filaments marked by e, e, e, e, e, e. Anthers f, f, f, f, f, f.

5. The pericarp, or seed-vessel, is the case or covering of the seed, and is the external part of the germen come to maturity. It is of various shapes; globular, as in the poppy; long, as in the pod of the common garden or field pea; it is pulpy, with a stone in the middle, as in the plum; pulpy, containing seeds enclosed in a case, as in the pear; juicy, and containing seeds which have only an external case, as the currant and gooseberry.

There are eight species of pericarp; capsule, silique, legume, follicle, drupe, pome, berry, and stroble. A description of these will be given in the vocabulary. Consult also Plate XCV. fig. 23. to 30.

6. The seeds are so well known, that they require no description in the elements of the science.

7. The receptacle is a point, line, or broad base, to which some or all of the six parts now described are attached. When it is the base of all these parts, it is called the receptacle of the fructification. When the calyx, corolla, and stamens only are attached to it, it is called the receptacle of the flower. When the germens together with the pistil only is fixed to it, it is called the receptacle of the fruit. It is called proper when only one flower with its fruit is inserted into it.

It is called common when many flowers are attached to it, as in the common daisies, dandelion. See Plate XCV. Fig. 13, c, a proper receptacle. Fig. 9, 10, a common receptacle.

Attention to the receptacle is most necessary chiefly in classes 11th, 13th, and 19th.

Besides these seven, which are called the parts of fructification, because when they exist together, they are supposed necessary for producing proper fruit, there is another part which Linnaeus calls the nectary, that requires attention, as it is the foundation of some genera. It is difficult for beginners to distinguish it, as it varies much in its appearance, and is not very discernible in a great many species. It is sometimes the name of a small gland; sometimes of a scale or a number of scales; sometimes of a cup; sometimes of a horn or spur on the corolla, as in larkspur and violet; sometimes of a groove or excavation. In short, it appears to be a name for any singular or irregular appearance of any of the parts of the flower. In all accurate and perspicuous systems, it is so well described that it can be easily found out. If this be done the name may be admitted, but if not it must lead to ambiguity and want of precision.

OF THE CLASSES.

The descriptions now given are sufficient to enable the young botanist to understand the classes and orders.

All plants are arranged into 24 divisions, called classes. In 23 of these classes, the flowers, or the pistils and stamens, or at least the stigmas and anthers, are evident. The 24th class comprehends all plants in which the flowers are invisible to the naked eye, as mosses, ferns, mushrooms.

The principles upon which the classes are formed are few, simple, and beautiful. All plants which have only one stamen, are of the first class; those that have only two, are of the second; those that have only three, are of the third: and so on, the number of stamens being the same with the number of the class in the first ten classes. See Plate XCIV. fig. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

In the next three classes, the place to which the stamens are fixed must be attended to as well as the number of the stamens. Thus the 11th contains those plants which have from 12 to 19 stamens inclusive, fixed to the receptacle. The 12th those that have 20 stamens fixed to the inside of the calyx. In this class the place of insertion is more to be relied on than the number of the stamens, for they are sometimes less than 20, often more. The 13th class comprehends those that have more than 20 stamens attached to the receptacle. See Plate XCIV. fig. 11, 12, 13. For an example of the 12th class a rose may be examined, and for an example of the 13th a poppy, or a ranunculus.

The 14th and 15th classes depend upon the number and proportion of the stamens. When there are four stamens in a flower, of which two are longer, it belongs to the 14th class. When there are six stamens, of which four are longer, it belongs to the 15th class. For an example of the 14th class the flowers of the dead nettle, mint, thyme, or foxglove, may be examined; The 16th, 17th, 18th, and 19th classes depend upon the manner in which the stamens are connected, whether they be joined by their filaments into one set, or two sets, or more than two; or be united by the anthers into a cylinder.

In the 16th class the stamens are united by their filaments into one set, forming a case round the lower part of the pistils, but separating at the top. A geranium forms a specimen of this class. In the 17th the corollas are papilionaceous, like the blossom of a bean; the stamens are connected by their filaments, but divided into two sets or parcels, one of which is thicker and forms a case round the pistil; the other is smaller and leans towards the pistil. Specimens of these may be found in the flowers of peas and beans. In the 18th class, the stamens are united by their filaments into more than two sets, or parcels. See Plate XCIV. fig. 18.

The 19th class is difficult to a beginner. It consists of compound flowers, as the common daisy, dandelion. They are called compound, because each single flower consists of a collection of little flowers or florets, attached to the same broad receptacle, and contained within one calyx. Each floret consists of a corollet, or little corolla, five stamens united by their anthers into a hollow or tubular cylinder, and a pistil which passes up through the tube of the cylinder. See Plate XCIV. fig. 19, and examine a dandelion, or thistle, or common groundsel, or a sunflower. See also the beginning of the 19th class in the system, where a fuller account will be given of this class.

In the 20th class, the stamens are attached to the pistil. An orchis will afford a specimen of this. See also Plate XCIV. fig. 20.

In the three next classes, the pistils and stamens are situated on separate flowers, or distinct plants, or on plants which bear flowers with pistils and stamens, others with stamens or with pistils, or flowers of both kinds.

The 21st class contains those plants which have flowers of different kinds on the same plant, some bearing pistils, and others bearing stamens only. The flowers with pistils we shall call pistillar or stigmatic, and those with stamens staminar or anthered. The birch affords an example of this class. See also fig. 21.

The 22d class consists of those species which have stamens on one plant and pistils on another. Instances of this may be found in the willow, poplar, and juniper. See fig. 22.

The 23d class comprehends those plants which have at least two and sometimes three kinds of flowers. 1. Some anther-stigmatic, or with pistils and stamens on the same flower. 2. Others have pistils only, or stamens only. 3. Or having flowers with pistils only, or flowers with stamens only. This may be expressed more concisely. Some having flowers anther-stigmatic, some stigmatic, or some anthered, or having both anthered flowers and stigmatic flowers. The common ash tree may be examined for a specimen of this class. See also fig. 23.

The names of the classes are formed from Greek words, and express the characteristic of each class. The first ten classes are named from the Greek numerals and the word *andria*, which the botanist must consider as synonymous with stamens.

1. Mon -andria. 2. Di -andria. 3. Tri -andria. 4. Tetr -andria. 5. Pent -andria. 6. Hex -andria. 7. Hept -andria. 8. Oct -andria. 9. Enne -andria. 10. Dec -andria. 11. Dodec-andria, 12 stamens. 12. Icos -andria, 20 stamens. 13. Poly -andria. 14. Di -dynamia, 2 powers. 15. Tetra -dynamia, 4 powers. 16. Mon -adelphia, one brotherhood. 17. Di -adelphia, two brotherhoods. 18. Poly -adelphia, many brotherhoods. 19. Syn -genesis means origin or production together, so called from the stamens being united by the anthers. 20. Gyn -andria, pistils and stamens together. 21. Mon-cecia, one house. 22. Di -cecia, two houses. 23. Poly-gamia, many kinds of flowers. The etymology here would throw no light upon the class to a beginner; nor does it throw any on the next class. 24. Crypto-gamia, therefore, is to be understood to mean invisible flowers.

OF THE ORDERS.

The formation of the orders is as ingenious and simple as that of the classes. In the first thirteen classes, the names and characters are taken from the number of pistils or styles; when these are wanting, from the number of stigmas. Thus:

- Mono -gynia, 1 style. - Di -gynia, 2 styles. - Tri -gynia, 3 styles. - Tetra -gynia, 4 styles. - Penta -gynia, 5 styles. - Hexa -gynia, 6 styles. - Hepta -gynia, 7 styles. - Deca -gynia, 10 styles. - Dodeca-gynia, 12 styles. - Poly -gynia, many styles.

In the 14th class Didynamia there are only two orders, which depend on the presence or absence of the pericarp or seed-vessel.

1. Gymnospermia. Four naked seeds in the bottom of the calyx; as in mint, dead-nettle, thyme.

2. Angiospermia. Seeds enclosed in a pericarp, as in fox-glove, eye-bright, toad-flax, fig-wort.

In the 15th class, Tetradynamia, there are also two orders, which are taken from the form of the pericarp.

1. Siliculosa. Seeds enclosed in a silicle, or roundish seed-vessel, consisting of two pieces called valves, and the seeds fixed to both edges or sutures, as in shepherd's purse, scurvy-grass.

2. Siliquosa. Elements. 2. Siliquosa. Seeds enclosed in a siliqua or long seed-vessel; as in mustard.

In the 16th, 17th, and 18th classes, the names and characters of the orders are taken from the number of stamens.

In the 19th class there are six orders, which it is difficult at first to distinguish accurately.

1. Polygamia Aequalis. Florets anther-stigmatic, or having both stamens and pistils in the same floret; as in dandelion, thistle, sow-thistle, artichoke.

2. Polygamia Superflua. When the flower is composed of two parts, a disk or central part, and rays projecting outwards; as in corn-marygold, tansy, daisy, golden-rod, groundsel, chamomile, milfoil. The florets of the disk are anther-stigmatic; those of the ray stigmatic.

3. Polygamia Frustranea. Florets of the disk anther-stigmatic; those of the rays with styles but no stigmas; as blue-bottle, knapweed.

4. Polygamia Necessaria. Florets of the disk anther-styled, without stigmas; those of the rays stigmatic. Garden marigold will afford a specimen.

5. Polygamia Segregata. When each of the florets has a calyx, besides the common or general calyx of the flower. Specimens of this can only be found in botanic gardens.

6. Monogamia. When the flower is not compound but single, and the anthers united. This order ought to be transferred to the class Pentandra, as, indeed, has been done in some very valuable systems. Examples of it may be found in the violet.

In the classes Gynandria, Monococcia, and Dioecia, the orders are formed from the number of stamens, with three of a different kind, monadelphia, syngenesia, and gynandria, in the classes Monococcia and Dioecia.

1. Monoecia. When the flowers are anther-stigmatic and anthered; or anther-stigmatic and stigmatic, on the same individual plant.

2. Dioecia. When the flowers are anther-stigmatic and anthered, or anther-stigmatic and stigmatic, on two different individual plants.

3. Trioecia. When the flowers of one individual plant of the same species are anther-stigmatic; upon a second individual plant, anthered; and upon a third individual plant, stigmatic.

The orders into which the 24th class, Cryptogamia, is divided, will be explained in the introduction to that class.

OF THE SECTIONS.

The orders are generally subdivided into what may be called sections. These may vary in number, according as the system is partial or universal; but they are almost as well established as the classes and orders. Sections are not employed in the 11th, 12th, 16th, 18th, 19th, 20th, 21st, 22d, 23d classes. The principles on which they are formed are few and very simple.

In the first ten classes they depend upon the following circumstances; on the flower being superior or inferior or naked, complete or incomplete, calycled, enclosed in a spathe or glume, aggregate, umbellated, involucrated; on the number of petals, the seeds being naked or enclosed; on the number of seeds, and the number of cells in the capsule or seed-vessel, or number of berries.

The flower is said to be superior when the receptacle of the flower is above the germen, and inferior when the receptacle is below the germen. A flower is said to be naked when the calyx is absent; it is called complete when it has both a calyx and corolla, and incomplete when either of these is wanting. It is said to be calycled when the calyx has a small calyx or calyxlet at the base. An aggregate flower, is a flower composed of florets standing on footstalks, attached to a broad receptacle.

An umbellated plant, is one which sends out towards the top, from the same point or centre, a number of branches like the spokes of an umbrella, and bearing flowers on the top. All the spokes, with their flowers, form an universal umbel. On the top of each spoke arises an umbellet, or partial umbel. At the base of the spokes of the umbel, or universal umbel, is a sort of calyx, called an involucre, or universal involucre; and at the base of the spokes of the umbellet is a partial involucre, or an involuculet. This will suffice for explaining the sections of the first ten classes. The sections of the 13th depend on the number of petals.

In the 14th class, Didynamia, the sections depend upon the calyx; which is said to be cleft when it is cut or divided into so many parts, and two-lipped when its mouth has a resemblance to two lips.

In the 15th class the sections depend on the silicle and calyx. The silicle in one section is notched at the point, and in another unnotched or entire. In the first section of the order siliquosa, the calyx is closed by its own leaflets. In the second it is not closed, and the leaflets are separated at the upper end.

In the 17th class, Diadelphia, and the order decandra, there are six sections. 1. The first comprehends those flowers which have their stamens all united as in the class Monadelphia, and therefore forms an exception to the regularity of the class. 2. In the second, the stigma is pubescent or hairy. The stamens not. 3. The seed-vessel or legume, has two cells, without the connected marks of the former sections. 4. The legume contains only one seed, without the marks of the former three sections. 5. The legume is somewhat jointed, without the marks of the former. 6. The legume has only one apartment, but many seeds, without the marks already mentioned.

The only remaining class, whose orders are divided into sections, is the 19th, Syngenesia. 1. In the first section of the first order, the corollets are ligulate, that is, flat towards the exterior or upper end, and tubular only at the base. 2. Capitate or headed, when the flowers grow in globular forms; as the thistle. 3. Discoid, when the corollets are all tubular, not ligulate. In the order polygamia superflua are two sections. 1. Discoid corollets. 2. Rayed or radiate, when all the corollets are ligulate. We will now present a connected view of the Classes and Orders in a Table.

I. MONANDRIA, 1 stamen. 1. Monogynia, 1 style. 2. Digynia, 2 styles.

II. DIANDRIA, 2 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles.

III. TRIANDRIA, 3 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles.

IV. TETRANDRIA, 4 stamens. If the two nearest stamens be shorter, the plant belongs to class 14th. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Tetragynia, 4 styles.

V. PENTANDRIA, 5 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Tetragynia, 4 styles. 5. Pentagynia, 5 styles. 6. Polygynia, more than 5.

VI. HEXANDRIA, 6 stamens. If the two opposite stamens be shorter, the plant is of the 15th class. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Tetragynia, 4 styles. 4. Polygynia, more than 4.

VII. HEPTANDRIA, 7 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Tetragynia, 4 styles. 4. Heptagynia, 7 styles.

VIII. OCTANDRIA, 8 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Tetragynia, 4 styles.

IX. ENNEANDRIA, 9 stamens. 1. Monogynia, 1 style. 2. Trigynia, 3 styles. 3. Hexagynia, 6 styles.

X. DECANDRIA, 10 stamens. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Pentagynia, 5 styles. 5. Decagynia, 10 styles.

XI. DODECANDRIA, 12 to 19 stamens, inserted in the receptacle. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Pentagynia, 5 styles. 5. Dodecagynia, 12 styles.

XII. ICOSANDRIA, 20 stamens or more fastened to the inside of the calyx. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Pentagynia, 5 styles. 5. Polygynia, more than 5 styles.

XIII. POLYANDRIA, more than 20 stamens fastened to the receptacle. 1. Monogynia, 1 style. 2. Digynia, 2 styles. 3. Trigynia, 3 styles. 4. Tetragynia, 4 styles. 5. Pentagynia, 5 styles. 6. Hexagynia, 6 styles. 7. Polygynia, more than 6 styles.

XIV. DIDYNAMIA, 4 stamens, 2 longer than the rest. 1. Gymnospermia, 4 naked seeds in the bottom of the calyx. 2. Angiospermia, seeds enclosed in a seed-vessel.

XV. TETRADYNAMIA, 6 stamens, 4 longer than the rest. 1. Siliculosa, seeds contained in a silique or roundish seed-vessel. 2. Siliquosa, seeds contained in a silique or long seed-vessel.

XVI. MONADELPHIA, stamens united by their filaments into one set or body. 1. Triandria, 3 stamens. 2. Pentandria, 5 stamens. 3. Octandria, 8 stamens. 4. Enneandria, 9 stamens. 5. Decandria, 10 stamens. 6. Endecandria, 11 stamens. 7. Dodecandria, 12 stamens. 8. Polyandria, more than 12 stamens.

XVII. DIADELPHIA, stamens united by their filaments into two bodies. 1. Pentandria, 5 stamens. 2. Hexandria, 6 stamens. 3. Octandria, 8 stamens. 4. Decandria, 10 stamens.

XVIII. POLYADELPHIA, filaments united and divided into more than two sets. 1. Pentandria, 5 stamens. 2. Icosandria, 20 stamens.

XIX. SYNGENESIS, anthers united into a cylinder. 1. Polygamia sequalis, florets all anther-stigmatic. 2. Polygamia superflua, florets of the disk anther-stigmatic; florets of the ray stigmatic. 3. Polygamia frustansca, florets of the disk anther-stigmatic; florets of the ray styled, but not stigmatic. 4. Polygamia necessaria, florets of the disk anther-styled; florets of the ray anther-stigmatic. 5. Polygamia segregata, several calyclets in one calyx. 6. Monogamia, flowers single, not compound, with anthers united.

XX. XX. Gynandria, stamens fastened to the pistils.

1. Diandria, 2 stamens. 2. Triandria, 3 stamens. 3. Tetrandria, 4 stamens. 4. Pentandria, 5 stamens. 5. Hexandria, 6 stamens. 6. Decandria, 10 stamens. 7. Dodecandria, 12 stamens. 8. Polyandria, more than 12 stamens.

XXI. Monoecia, stamens and pistils not in the same flowers, but in the same plant.

1. Monandria, 1 stamen. 2. Diandria, 2 stamens. 3. Triandria, 3 stamens. 4. Tetrandria, 4 stamens. 5. Pentandria, 5 stamens. 6. Hexandria, 6 stamens. 7. Heptandria, 7 stamens. 8. Polyandria, more than 7. 9. Monadelphia, filaments united. 10. Syngenesia, anthers united. 11. Gynandria, stamens fixed to pistils.

XXII. Dioecia, stamens and pistils on different plants.

1. Monandria, 1 stamen. 2. Diandria, 2 stamens. 3. Triandria. 4. Tetrandria. 5. Pentandria. 6. Hexandria. 7. Octandria. 8. Enneandria. 9. Decandria. 10. Dodecandria. 11. Polyandria. 12. Monadelphia. 13. Syngenesia. 14. Gynandria.

XXIII. Polygamia.

1. Monococcia, anther-stigmate and stigmate, or anthered in the same plant. 2. Dioecia, anther-stigmate and stigmate, or anthered in two plants. 3. Tricoccia, anther-stigmate in one plant, stigmate in a second, and anthered in a third.

XXIV. Cryptogamia.

1. Filices, or ferns. 2. Mosses. 3. Algae, or sea-weeds. 4. Funguses.

OF THE GENERA.

Having now shown how plants are arranged into classes, orders, and sections, we come to the next division, called genera. The characteristic marks of the genera are derived from the flower and fruit. A genus consists of a certain number of species, which resemble one another in some parts of the flower or of the fruit, or both. By way of illustrating the principles on which the formation and distinction of genera are founded, we shall run over the British genera in each class.

I. In the first class, Order I. sect. 1. the calyx is Element. one-leaved or indistinct, corolla absent. Sect. 2. the berry contains many seeds, the spadix contains many flowers, and the capsule is one-seeded. Order II. genus 5. calyx wanting, two petals present; seeds four, not enclosed in a seed-vessel.

II. In the 2d class, Diandria, Order I. the genera depend upon the figure of the corolla, which is divided, wheel-shaped, ringent, furnished with a spur, or two-petaled; on the calyx being cleft or being two-leaved; on the number of seeds which the berry contains; on the shape of the capsule, and the number of seeds enclosed in it; on the stamens being distant, or standing on a footstalk.

In the 2d order, the only genus is a grass, the calyx and corolla of which are called glumes.

III. In the 3d class, Triandria, Order I. sect. 1. the distinction of the genera depends on the number of divisions of the calyx and singularities of the stigma. In sect. 8. the genera are distinguished by the peculiarities of the glumes and seeds.

In the 2d order, Digninia, sect. 1, 2, 3, and 4, the genera are distinguished,

1. By the number of valves or pieces of which the glumes or corolla and calyx consist. 2. By the peculiarities of these valves. 3. By the number of flowers contained in the calyx. 4. By the peculiarities of the stigma and seed. 5. By the form of the spikelets, and 6. By the peculiarities of the spine or thread, or form of the receptacle.

In the 3d order, Trigynia, the genera are distinguished,

1. By the number of leaves of which the calyx is composed. 2. By the number of petals. 3. By the form of the capsule, the number of valves composing it, and seeds contained in it.

IV. In the 4th class, Tetrandra, Order I. the genera are determined,

Sect. 1.

1. By the peculiarities of the common and partial calyx, or of the calyx and calyclet. 2. By the corolla being superior.

Sect. 2. and 3.

1. By the form of the corolla, 2. By the peculiarities of the fruit.

Sect. 4.

1. By the number and the peculiarities of the nec- taries. 2. By their absence. 3. By the nature of the seed-vessel; by its situa- tion, and the number of cells or seeds it con- tains.

Sect. 5.

By the peculiarities of the calyx and seed.

Digninia and Trigynia, Order I. and II.

1. By the number of petals, and by their ab- sence. 2. By the nature of the pericarp, and by the num- ber of its valves and cells, and seeds.

V. In the 5th class, Pentandra, Order I. the ge- nera are distinguished, Sect. I.

1. By the shape of the corolla, by the peculiarities of its throat. 2. By the shape of the calyx, and the number of its divisions. 3. By the peculiarities of the seeds.

Sect. 2, 3, 4, and 5.

1. By the number of valves and cells of the seed-vessel, and other peculiarities. 2. By the shape and division of the corolla. 3. By the situation and figure of the stamens and peculiarities of the anther. 4. By the divisions and shape of the stigma. 5. By the shape of the calyx and number of its divisions.

Sect. 6.

1. By the number of seeds and situations of the capsule. 2. By the number of divisions of the calyx, and its relation to the stamens.

Dignia, the genera are distinguished,

Sect. 1, 2, and 3.

1. By the nature and shape of the capsule, and the number of cells and seeds it contains. 2. By the shape of the corolla and the absence or presence of pores. 3. By the shape, number, and situation of the seeds.

Sect. 4, comprehending the umbelled plants, is formed into three subdivisions.

1. Plants that have an involucre and involucret. 2. Those that have only involucrets. 3. Those that have neither, or only a small involucre.

The genera are distinguished,

1. By the flowers being formed into heads. 2. By the flowers being tubular, by being radiate or rayed, that is, some tubular and some flat, by their being fertile or abortive, producing seed or not producing it. 3. By the form of the petals. 4. By the calyx being entire or divided, or indistinct. 5. By the peculiarities of the involucres or involucrets. 6. By the peculiarities of the stigmas and fruit.

The other orders have nothing peculiar.

VI. Hexandria, the genera are distinguished,

1. By the number of petals, shape, divisions, and situation of the corolla. 2. By the number of leaves, form, and situation of the calyx. 3. By the number of cells and seeds of the seed-vessels, and shape of the seed. 4. By the peculiarities of the stamens. 5. By the form and number of the stigmas.

The next seven classes form their genera in so similar a manner to those already described, that we omit them.

XIV. In the 14th class, Didynamia, Order I. Gymnospermia, the genera are determined,

1. By peculiarities of the anthers and filaments. 2. By peculiarities of the lips and throat of the corolla. 3. By peculiarities of the calyx.

Order II. Angiospermia.

1. By the number of cells and directions of the partitions of the capsule or seed-vessel. 2. By the form and number of the seeds. 3. And by other marks of the calyx and corolla, which require no explanation.

XV. Tetradynamia.

I. Siliculosa, the genera are distinguished,

1. By the silicle or short roundish seed-vessel, by the shape and position of its valves or pieces, by its being entire or notched, and the number of seeds it contains.

II. Siliquosa. The genera are distinguished,

1. By the shape of the silique or long seed-vessel, which is composed of two valves or pieces, with the seeds fastened to both sutures, or joinings of the valves; by the manner in which the silique opens. 2. By peculiar glands. 3. By the calyx being open or spreading. 4. By the position of the petals. 5. By the stigma being notched or entire.

XVI. In the 16th class, Monadelphia, the genera are distinguished,

1. By the number of styles. 2. By the divisions of the outer calyx. 3. By the position of the capsules and number of seeds contained in each. 4. By the seeds being beaked spirally or backwards.

XVII. Diadelphia. Here it is necessary to describe the corolla, which is called papilionaceous, or pea-blossomed, and usually consists of four petals. The lower petal, shaped like a boat, is called the keel; the upper petal, which spreads and rises upwards, is called the standard, and the two side petals are called the wings. The seed-vessel is called a legume, and consists of two pieces or valves, and the seeds are fixed to one of the sutures or joinings.

In the order Decandria, the genera are distinguished,

1. By the form and divisions of the calyx. 2. By the form and roughness of the style and stigma. 3. By the peculiarities of the standard, keel, and wings. 4. By the legume; its form, length, and the number of seeds it contains.

XIX. In the 19th class, Syngenesia, the genera are distinguished,

1. By the nature and form of the receptacle, by its smoothness or roughness, its being dotted, or like a honeycomb. 2. By the nature of the pappus, which is the feathery, or flying, or winged crown of the seed by which it flies. 3. By the peculiarities of the calyx, its resembling tiles, being double, accompanied with scales, &c. 4. By the number of florets in the ray.

XX. Gynandria, Diandra, the genera are distinguished,

By the form of the nectary, which is the lower lip of the corolla.

XXI. In the 21st class, Monoecia, the genera are distinguished,

1. By 1. By peculiarities in the male or anthered flower of the calyx and corolla.

2. By similar peculiarities in the female or stigmatic flowers.

3. By the form of the ament. The ament is a species of flower consisting of a thread-form receptacle, to which a number of chaffy scales are attached. A specimen of it may be seen in the flowers of the fir, birch, hazel, beech, and oak.

XXII. XXIII. In the 22d and 23d classes, Dioecia and Polygamia, the genera are distinguished in a manner similar to those already described. We have only to remark, that what in other systems are called hermaphrodite flowers, in the class Polygamia we call anther-stigmatic, or pistil-staminal, that is, flowers having both anthers and stigmas, or pistils and stamens.

OF THE SPECIES.

The species consist of such groups or collections of plants as have certain resemblances, which render it convenient to class them under one genus. The species are distinguished from one another, either by marking in a few words the most striking differences, or by giving a minute description of each species. In the foreign plants, we have adopted the first method for the sake of brevity. But in the British, which it is of consequence we should study more perfectly, we have adopted the second. The first is a translation of Willdenow's Species Plantarum, the most complete system hitherto published, and the second, or the description of the British plants, is a translation from Dr Smith's Flora Britannica, which we have no hesitation in saying is a model of botanical description. For precision it is worthy of Linnaeus, and is so minute that nothing peculiar to any species seems to have escaped the author.

The species, when numerous, are formed into subdivisions. This we think should always be done, when it can be done with propriety. There are some eminent botanists who disapprove of this practice, because, say they, it separates species that have the closest resemblance to one another. This, however, is of no consequence; for it is not the object of botanical arrangement to place these plants next one another, which are most like; but to point out the species, and most certain method of discovering the names of such plants as we have occasion to examine. We cannot help regretting, therefore, that Mr Salisbury, in his new arrangement of Erica, a genus consisting of more than 240 species, should, in order to class them according to their affinities, have neglected to form them into subdivisions: the subdivision of the species diminishes the unnecessary labours of the botanist, and tends to increase the precision of inquiry. For example, 32 species of the campanula have leaves smooth polished, and the rest have leaves rough to the touch. This circumstance forms a very convenient subdivision. Again, 44 species of the solanum have neither prickles nor thorns, 39 are pricked, and one is thorny or spinous. Thus, in examining a solanum, we can have no occasion to run over 84 species; we are required only to go over 44, or 39, or one. There is as much propriety in forming the numerous species of a genus into subdivisions, as there is in separating plants that have a close resemblance into different genera. Who would have supposed that the botanist who has separated the Erica vulgaris or common heath, from the genus to which it has hitherto belonged, would have thought it improper to arrange so extensive a genus into subdivisions. We can only account for it, by supposing that an eminent botanist may sometimes forget the principles of the Linnean classification, to seek after a natural classification; a thing which we suspect is like the government of Utopia, that exists only in the mind of the inventor.

OF VARIETIES.

Every part of a plant is subject to variation from climate, soil, cultivation, and diseases, or injuries produced by insects, winds, &c. The corolla and leaves are most liable to change. Variations arising from such accidents are not permanent; they may indeed be propagated by slips, but vanish in those plants which are raised from seeds. It is by rearing plants from seeds that we can determine whether a plant be a variety or a distinct species.

RULES FOR DIRECTING THE YOUNG BOTANIST IN INVESTIGATING A PLANT.

After the young botanist understands the principles upon which the classification is formed, he ought immediately to proceed to the examination of plants.

1. The botanist ought to select flowers in different states, some expanded, some unopened, and if possible, some that are ripened into fruit.

2. If the flower contain both stamens and pistils, it belongs to some one of the first 20 classes. If either the pistils or stamens be wanting, it belongs to the 21st, 22d, or 23d. To this rule there are a few exceptions, which if the young botanist cannot overcome, he may pass them over till he has made some progress in the art of investigation.

3. He must next examine whether the stamens be connected or separate, and whether two of them be uniformly shorter than the rest. If the stamens be not connected, and two of them be not uniformly shorter, the plant belongs to one of the first 13 classes. If the stamens do not amount to 12, the number of the stamens and number of the class is the same. If the stamens be 12 or more, then, besides counting them, it is necessary to observe whether they be fixed at the lower end to the calyx or receptacle. This may be best known by tearing off the calyx; if the stamens do not come away with the calyx, the plant belongs to the class dodecandra. If the stamens be about 20, less or more, and fixed to the calyx, the plant belongs to icossandra. If 20 or more, and attached to the calyx, the class is polyandra.

In all these classes the orders may be known by examining the pistils.

4. If the stamens be four or six, and two shorter than the rest, the plant belongs to didynamia or tetradynamia. The corolla in didynamious plants is one petal divided into two lips; and the corolla of tetradynamious plants consists always of four petals, placed somewhat in the form of a cross: hence called cruciform.

The orders of the class didynamia may be known by observing whether the seeds be enclosed in a seed-vessel, In tetradynamia, the orders are distinguished by the form of the seed-vessel. If long, the order is siliquosa; if roundish it is siliculosa.

5. If the stamens be connected by the filaments into one set round the pistil, but separated at the top, and the petals five, the class is monadelphia. If the stamens be formed into two sets, and the corolla like the blossoms of a pea or bean, the class is diadelphia; and if formed into more than two sets, the class is polyadelphia. The orders depend upon the number of the stamens.

6. If the flower be compound, that is, if one calyx contain a great many corollets, each of which has five stamens united to a cylinder at the anthers, the flower belongs to the class syngenesia.

The orders are to be determined by examining the florets, that is, the corollets of the disk and ray, in order to know whether they both contain pistils and stamens, or anthers and stigmas, or otherwise: 1. If all the florets contain stamens and a pistil, the order is polygamia equestris. 2. If the disk or central part have florets with a pistil and stamens, but the rays contain only a pistil, the order is polygamia superflua. 3. If the florets of the disk have stamens and pistils, or be another-stigmatic, but those of the rays have only a style, the order is polygamia frustacea. 4. If the florets of the disk have stamens and styles, but no stigmas, and those of the rays a pistil only, the order is polygamia necessaria. 5. When each of the florets has a small calyx, the order is the polygamia segregata. 6. And when the flower is not compound, but single with anthers united, the order is monogamia. But such plants are commonly now added to the class pentandra.

7. If the stamens be fixed to the pistil, the class is gynandria. The flower has something of a monstrous or irregular appearance. The petals are five, the style grows from the inner petal of the lower lip of the corolla, so as scarcely to be distinguishable.

The orders are determined by the number of the stamens.

8. When the flowers are imperfect, that is, when some in the same individual plant have only pistils and some only stamens, the plant belongs to the class monococcia. When the pistils are in one plant, and the stamens on another, the class is dicoccia; and when perfect and imperfect flowers occur on the same plant, or on two or three different plants, the class is polygama.

The orders of monococcia and dicoccia, are known by the number of stamens; and in polygama, if imperfect and perfect flowers, that is, anther-stigmatic, and stigmae or anthered, be found on the same plant, the order is monococcia; if on two plants, the order is dicoccia; and if anther-stigmatic flowers be on one plant, stigmae on another, and anthered on a third, the order is tricoccia.

9. Different flowers should be examined, and especially those that are unopened, if the number of stamens and pistils should vary. And if after this examination, different unopened or unexpanded flowers should vary, a preference should be given to the flowers that terminate the stalk. We ought always, therefore, to compare different flowers before we inquire after the class or orders.

II. 1. After determining the class and order, the botanist ought to compare with the flower which he is investigating the different sections of the order when it is divided into sections. He may then proceed to examine the genus.

2. In the beginning of each class he will find all the genera arranged as they agree and differ in some essential characters of the flower and fruit. But they are numbered in that order which brings those that have the closest resemblance next to one another. After the section is determined, then the flower must be compared with each of the genera of that section, or of the order when it is not divided into sections.

3. If none of the essential characters agree with the flower and fruit of the plant which is examined, then the plants which are named at the end of the orders are to be sought for and examined.

In this system we have first given the essential marks of all the genera at the beginning of each class in Latin, and also in English.

4. After determining the genus, the plant may be compared with the description of the species. In foreign plants we have in general given only the essential character of the species. But in some British plants we have added also, from Dr Smith's Flora Britannica, a minute and fuller account, as an example of botanical description.

We have not referred to those books which give plates of the species, because they are accessible but to very few, and because we do not think that a man will ever be a botanist whose knowledge is indebted to plates. It is much better to consult an experienced botanist than a book of plates. Those, however, who wish to consult plates may do so from this system as well as from any other, after ascertaining the class and order.

As to the language which is employed in the following system, we need say very little. We have endeavoured to make it as much English as possible. We have always preferred words of English origin when we thought them sufficiently accurate; but when we had reason to believe that such words were so vague that they might lead into error, we thought it better to adopt the Linnean terms, and to give them an English termination. In a few cases we have retained the Linnean terms unaltered, as corolla, bractea, stipula, because we thought any such change would be unpleasant to the ear, as corol, bracte, stipule. Besides, it would be no disadvantage to the harmony of our language to have more words ending with vowels.

We once intended to have given English names to many of the genera, and to all the species, and had done so through the first four or five classes; but it was objected, that this would increase the synonymes, which are already too numerous; and consequently would often tend to mislead than to be useful. It would certainly be much better that plants were known in all nations by the same name.

Of the Method of forming an Herbarium or Hortus Siccus.

Every man who wishes to be a complete botanist will find it necessary to preserve and to form into a collection the plants which he has examined. The best method of preserving them is by drying them; specimens ought to be collected when dry, and carried home in a tin box. Plants may be dried by pressing, in a box of sand, or with a hot smoothing iron. Each of these has its advantages.

1. If pressure be employed, a botanical press may be procured. The press is made of two smooth boards of hard wood, 18 inches long, 12 broad, and two thick. Screws must be fixed to each corner with nuts. If a press cannot easily be had, books may be employed.

Next, some quires of unsized blossom blotting paper must be provided. The specimens, when taken out of the tin box, must be carefully spread on a piece of pasteboard covered with a single sheet of the blossom paper quite dry; then place three or four sheets of the same paper above the plant, to imbibe the moisture as it is pressed out; it is then to be put into the press. As many plants as the press will hold may be piled up in this manner. At first they ought to be pressed gently.

After being pressed for twenty-four hours or so, the plants ought to be examined, that any leaves or petals which have been folded may be spread out, and dry sheets of paper laid over them. They may now be replaced in the press, and a greater degree of pressure applied. The press ought to stand near a fire, or in the sunshine. After remaining two days in this situation, they should be again examined, and dry sheets of paper be laid over them. The pressure then ought to be considerably increased. After remaining three days longer in the press, the plants may be taken out, and such as are sufficiently dry may be put in a dry sheet of writing paper. Those plants which are succulent may require more pressure, and the blossom paper again renewed.

Plants which dry very quickly, ought to be pressed with considerable force when first put into the press; and if delicate, the blossom paper should be changed every day. When the stem is woody it may be thinned with a knife, and if the flower be thick or globular, as the thistle, one side of it may be cut away; as all that is necessary, in a specimen, is to preserve the character of the class, order, genus and species.

2. Plants may be dried in a box of sand in a more expeditious manner, and this method preserves the colour of some plants better. The specimens, after being pressed for ten or twelve hours, must be laid within a sheet of blossom paper. The box must contain an inch deep of fine dry sand, on which the sheet is to be placed, and then covered with sand an inch thick; another sheet may then be deposited in the same manner, and so on, till the box be full. The box must be placed near a fire for two or three days. Then the sand must be carefully removed, and the plants examined. If not sufficiently dried, they may again be replaced in the same manner for a day or two.

3. In drying plants with a hot smoothing iron, they must be placed within several sheets of blotting paper, and ironed till they become sufficiently dry. This method answers best for drying succulent and mucilaginous plants.

4. When properly dried, the specimens should be placed in sheets of writing paper, and may be slightly fastened by making the top and bottom of the stalk pass through a slip of the paper, cut neatly for the purpose. Then the name of the genus and species should be written down, the place where it was found, nature of the soil, and the season of the year. These specimens may be collected into genera, orders, and classes, and titled and preserved in a portfolio or cabinet. The method of preserving many of the cryptogamous plants is more difficult, on account of the greater quantity of moisture which they contain, and the greater delicacy of their texture.

We will now conclude this introduction with particular reference to the plates.

EXPLANATION OF THE PLATES.

Plate XCIV. exhibits the 24 CLASSES; fig. 1. representing the first class, or Monandria; fig. 2. the second class, or Diandria; fig. 3. the third class, or Triandria; and so on, according to the enumeration in the table.

Plate XCV. represents the parts of a plant upon which the investigation of the GENUS depends.

Parts of the Flower.—Fig. 1. Spathe. Fig. 2. Spadix. Fig. 3. Gluma, or glume; b, arista, or awn. Fig. 4. Umbella and involucrum; a, Umbella universalis, or universal umbel; b, partialis, or partial umbel; c, Involucrum universale, universal involucre; d, partiale, or partial involucre. Fig. 5. Calyptra, calyptre or veil; a, capitulum; b, operculum; parts of mosses. Fig. 6. Amentum. Fig. 7. Strobilus, strobile. Fig. 8. a, Pileus, cap; b, volva; c, stipes; parts of fungi or mushrooms. Fig. 9. a, Receptaculum commune nudum, the common receptacle or base of the flower when the stamens, pistillum, capsule, &c. are taken off. Fig. 10. Receptaculum commune paetis imbricatum, or common receptacle imbricated with paleae or membranaceous lamella. Fig. 11. a the tube, b the edge or margin, of a one-petaled corolla. Fig. 12. is a flower laid in a proper position for showing its different parts. a, Germen, which includes the seeds and capsule in which they are enclosed; b, style, a continuation of the germen; c, stigma, or top of the stylus; d, filaments, or threads; e, e, e, e, anthers; f, f, f, f, petals. Fig. 13. a, the claws, b, the laminae or plates, of a many-petaled corolla. Fig. 14. a, Bell-shaped nectary of the narcissus. Fig. 15. Horned nectaries of monkshood. Fig. 16. Horned nectary in the calyx of the tropocolum. Fig. 17. a a a a, The nectaries of the parnassia grass, five in number, each of which has 13 styles, with round buttons on their tops.

Parts of Fructification.—Fig. 18. a, Perianth; b, germen; c, style; d, stigma; e, filaments; f, anthers, some shedding the pollen or dust; g, the appearance of the anther before it sheds the pollen. Fig. 19. a, the filament, and b, the anther, separated from the flower. Fig. 20. a, one grain of the pollen magnified by a microscope; b, an elastic aura supposed to be necessary for impregnating the seeds. Fig. 21. a, Germen; b, style; c, stigma. Fig. 22. Follicle: The seeds not adhering to the suture, are enclosed in a particular receptacle, a. Fig. 23. Legume, or a double-valved pericarp, having the seeds fixed only to one of the sutures a a. Fig. 24. Silique, or a double-valved pericarp, with the seeds fixed to both sutures or margins, a b. Fig. 25. Pome, or a fleshy pericarp, containing