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At the base of many leaves are a pair of scales called stipules; the petiole or leaf-stalk is generally cylindrical, but frequently triangular, and in grasses it is flat and surrounds the stem, this is called a sheath; when leaves are narrow and not expanded into a lamina, as in the pine tribe, they are said to be "acicular."

The stalks which bear the flowers are called "pedicels," at the base of which are a pair of scales called "bracts;" when these are large and expanded, so as to enclose the flowers, they are called "spathes" (this is seen in the arum), and when there are a number of flower-stalks arising from one point the bracts there collected are called an "involucre." A flower consists of several parts, the outermost green scales, composing a set, are called the calyx, and each part of it, is called a "sepal," within this is the "corolla" or that coloured part which forms the most characteristic feature of the flower, each part of the corolla is called a "petal;" when the corolla consists of but one piece, it is called "monopetalous," and when of many, "polypetalous."

The forms of corolla vary according to the form and the mode in which the petals are placed, whether united or separated, and to what extent, whether regular or irregular; the most usual forms are the following:—

Within the corolla are placed the "stamens" (male reproductive organs) these consist generally of two parts, the head and stalk, the former called the "anther" and the latter the "filament," which last is sometimes absent, and the anther is said to be "sessile;" on the surface of the anther is the "pollen" or fertilising dust.

Within the centre of the flower is the "pistil" (female reproductive organ), this consists of one or several cells called "ovaries," from the pistil a tube rises, having an expanded end called the "stigma," it is by the application of the pollen dust to this stigma that the ovaries are fertilised, and the various insects, especially bees, who seek for honey, shake off by their movements the pollen from the anthers and cause it to be applied to the stigma, thus unconsciously performing a necessary office for the plant while they rob it of that only which is not required.

The stamens are sometimes separate, sometimes bound up into one or more bundles, and are placed in various situations, names are given to describe such arrangements as follows:—

Stamens in one bundle, Monadelphous.
Stamens in two bundles, Diadelphous.
Stamens in more than two bundles, Polyadelphous.
Filaments placed directly below the pistil, Hypogynous.
Placed upon the sides of the calyx, Perigynous.
On the sides of the corolla, Epipetalous.
On the top of the ovary, Epigynous.

When the ovaries are fertilised the flower dies and they begin to enlarge and ripen to form the fruit, which is the pistil enlarged, and contains the ovules ripened into seeds.

The fruits of different plants are known by various names according to the state of development of the various parts composing them. If the ripe fruit split open so as to let out the seeds (as in the common pea) it is called "dehiscent," if it do not so split (as in the apple) it is said to be "indehiscent;" the outer part of fruit is called the "pericarp," and this may be soft and fleshy as in the apple or cherry, or hard as in the filbert. The following are the names of the principal varieties of fruit:—

The seed is the ovule ripened, it contains the germ of the future plant, called the "embryo," the outer part of the seed is called the "testa," and the space between this and the embryo is generally filled with starchy matter called the "albumen." The embryo consists of the plumule or stem, the "radicle" or root, and the cotyledons or leaves of the future plant; when the seed has but one cotyledon it is called "monocotyledonous" and when it has two "dicotyledonous."

Flowers are arranged in various ways upon the plants which produce them, and receive names accordingly; the whole arrangement of flowers is called the "inflorescence."

The following are the principal forms of inflorescence:—

The vegetable kingdom is divided into three great natural families, the AcrogenÆ, the EndogenÆ, and the ExogenÆ.

The acrogenous plants are those which as a general rule have neither branches, leaves, nor flowers; they are almost wholly made up of cellular tissue, and are many of them so minute that they are quite invisible individually to the unassisted eye, and are among the most wonderful works of the Creator, having an amount of beauty in form and elaboration of ornament bestowed on them, quite equal to anything among the higher and larger creations, and yet some of these are so small that tens of millions may be placed in the space of a cubic inch, of such are the DiatomaceÆ and DesmidiaceÆ.

The acrogens take an immense range in the scale of organisation, from the ferns (which appear but little inferior to the exogenÆ or endogenÆ, have stems and leaves, and in some cases, as in hot and moist climates, assume the size and form of a tree), to the very lowest state of vegetable existence, consisting of simple cells uniting into strings or forming simple threads, such as the green algÆ which form on stagnant waters and damp ground or wood-work, and the mould or mildew which forms on all decomposing substances. The general name for these acrogens, "cryptogamia," which has been in use for a long time and is commonly still used, indicates that the reproductive organs are invisible, hence the expression used by one of Shakespeare's characters, "We have the secret of fern seed, we walk invisible;" but this is not really the case, for the "sorri" at the back of fern-leaves, are vessels filled with spore cases each having a number of angular seeds within it; the lower tribes of the acrogens do not commonly grow from seed but by an extension of their several parts by the development of the cells of which they are composed, and by their separation into portions.

Few of this tribe have anything like true woody texture, except their highest order, the ferns, which form some of the most beautiful objects in the vegetable world. Few of the family of acrogens are of much direct use to man, the mushroom tribes are very generally eaten where they abound, the lichens of the arctic regions form the food of the reindeer (the greatest friend of man in these cold climes) as well as, in part, the food of man himself; but although these lowly plants serve man but little, directly, there is not a shadow of doubt that they have as important an office to fulfil as any other family or tribe of organised creatures, whose purpose may meet the eye more plainly. For all the members of creation form, as it were, the links of one great chain, and were but one removed, though it might perchance be only some poor weed or lowly moss, yet might it cause the whole to be annihilated; for certain earthy matters enter into the structure of all plants, and it appears to be the wonderful office of some of these lowest tribes of plants to prepare this earthy matter for its reception into the systems of higher organisms, for as silica is one of the primitive rocks of the earth and is only found in fragments, from the largest to the sand on the sea-shore, which is nothing but a collection of minute fragments of quartz worn small by attrition, yet a grain of sand is a gigantic mass of rock in comparison with the thin porous hollow shells of the DiatomaceÆ, &c., and by far too large to be absorbed or dissolved so as to be taken into the systems of other plants that may require it, which plants would cease to exist if this earth were not thus prepared for them; now these are the corn-bearing plants, the most useful to the animal world, and upon which it in reality depends for existence. Moreover the whole of the mould in which the higher orders of plants grow, is formed by the decomposition of the more humble grades, especially the lichens, which first take possession of the surface of bare rocks and stones, and furnish by their death food fit for the sustenance of those which follow them. Like the higher orders of vegetation, these minute plants excrete oxygen, and thus in the ocean may supply this vital element for the respiration of the various corresponding minute animal organisms which inhabit the depths of the sea and which cannot come to the surface to get it, so that the two thus supporting each other, form food for all the higher marine animals, which are finally eaten by man. So that upon some of these minute and apparently useless creatures hang the lives and well-being of many of the most important vegetables and animals.

Dr. Lindley divides the acrogens into the following orders:—

1. AlgÆ (Algals), including Sea-weeds, &c.

The AlgÆ include the lowest of all the vegetative organisms, the "Protophytes" (first plants). These have no individual parts, but consist of living cells, propagating by sub-division or by the union of two cells into one, causing the formation of "nuclei" or smaller cells within them, each of which becomes a parent cell after the rupture of the cell-membrane which contained them.

Dr. Carpenter, in his "History of the Microscope," says:—"The life-history of one of these uni-cellular plants in its most simple form, can scarcely be better exemplified than in the Palmogloea macrococca, one of those humble forms of vegetation which spreads itself as a green slime over damp stones, walls, &c. When this slime is examined with the microscope, it is found to consist of a multitude of green cells, each surrounded by a gelatinous envelope; the cell, which does not seem to have any distinct membranous wall, is filled with granular particles of a green colour, and a 'nucleus' may sometimes be distinguished through the midst of these. When treated with tincture of iodine, however, the green contents of the cell are turned to a brownish hue, and a dark-brown nucleus is distinctly shown. Other cells are seen, which are considerably elongated, some of them beginning to present a sort of hour-glass contraction across the middle; in these is commencing that curious multiplication by duplicative subdivision which is the mode in which increase nearly always takes place throughout the vegetable kingdom."

The higher tribes of AlgÆ embrace the sea-weeds; these are for the most part broad, leaf-like expansions of "thallus," composed of cellular tissue, they sometimes grow to an enormous length. Humboldt mentions the sea-grass as extending for miles, and forming continuous extensions of two or three hundred feet, and the Macrocystis pyrifera attains to the length of more than a thousand. The common Bladder-wrack (Fucus vesiculosus) was formerly much used to procure soda from, its ashes containing a considerable quantity, it is also used for manure; the Laminaria digitata is eaten under the name of "tangle," and a nutritious jelly is made from the "Carigeen moss" (Chondrus crispus).

3. Fungi (Fungals), including Mushrooms, &c.

The Fungi comprise a great variety of vegetable growths, from the mould which grows on any animal or vegetable substance, to the mushroom. Some of the moulds or mildews found on various decaying substances are peculiar to them, and in many cases exceedingly destructive. The microscopic fungus Puccinea graminis, is the parasite which fixes itself to corn and produces the disease known as mildew, and the Uredo segetum (another microscopic fungus) causes the "smut;" the "bunt" is caused by the Uredo foetida, and the "spur," or "ergot," which attacks rye, is caused by the Acinula clavis. These fungi completely destroy the grain of corn, in which they form, and propagate in the most rapid manner; the ergot is moreover a dangerous poison to those who eat the bread made of rye infected by it. The Truffle (Tuber cibarium) is a kind of underground fungus, and is esteemed a dainty. Mushrooms are also fungi, and several species are sufficiently wholesome; these are the Field Mushroom (Agaricus campestris) and the Fairy-ring Mushroom (Agaricus pratensis).

4. Lichenes (Lichens),

Are those dry scaly growths forming grey, green, or yellow spots on the barks of trees and in various other places, and they grow in a sort of leaf or scale called a "thallus." They are used as articles of food and as "dye-stuffs;" the Cetraria Icelandica is the "Iceland Moss" used here for making a sort of nutritious drink or jelly, the natives of Iceland, however, use it as common food; the Cladonia rangifarina, or Reindeer Moss, is the chief food of that useful creature which forms the whole property of the Laplander; and the Roccella tinctoria is the substance from which the dye called "archil" is procured.

5. Filices (Ferns).

The Ferns are a very numerous order of acrogenous plants, growing in the temperate regions from a rhizome or underground stalk (commonly called its root), which throws up "fronds" or leaves with a strong midrib; this midrib is commonly called its stalk, but in tropical countries the fern stalk rises above ground to the height of 30 or 40 feet, and then it is seen that the ordinary stalks are but the midribs of the fronds. There are between two and three thousand species of fern. The fronds open in a peculiar manner, unwinding as it were from a round ball. The "sorri" or seed-cases are situated at the back of the fronds in little brown spots, each of which is found to consist of a heap or collection of round capsules, and if these be placed under the microscope they have the appearance of little membraneous cases covered with net-like markings, and at the upper part a striated band of a brown colour, which after a time stretches out into a nearly straight line, tearing open the bag or capsule, and a number of seeds escape. Ferns grow best in damp and shady situations, and will thrive well in damp mould under a glass case.

The second division of the vegetable kingdom are the EndogenÆ, which are those plants growing from a central bud only, as the palms, bamboos, and canes of all kinds, the grasses and all graminiferous or grain-bearing plants, as wheat, barley, &c. They have but one cotyledon in the seed and have no bark, but in place thereof a kind of natural varnish or thin coating of silica; this varnish or external polish is seen in the stalks of corn and on canes. Their leaves are often of great size, the veins run parallel to each other (fig. 8), they often grow from an expanded base which surrounds the stalk as in corn, and branch off at regular intervals making knobs or joints, as may be seen in the bamboo cane (figs. 9 and 10), in other cases they branch off spirally, and when fallen form a sort of trellis-work on the stem (as in some of the palms) but always in a regular manner. The wood of this family of vegetables has the same porous structure as cane (figs. 11, 12, 13,14), and is often hollow in the centre, becoming more and more solid according to the age of the tree. The stems of these plants are limited in growth and soon acquire their full size, which never exceeds eighteen or twenty inches in dia meter although some of the palms are nearly 150 feet high. When the stem has acquired its full size, the continual production of more woody fibres makes it impossible that these (like the exogenÆ) can have a very extended period of existence, for when every part of the stem is full of woody matter, the plant ceases to grow from obstruction to the circulation of the juices. The stems of some of this family are always hollow like the stalks of corn; this arrangement allows of great elevations without bending, and is found to be the form which gives the greatest strength from a given quantity of material—one of those beautiful mechanical perfections of nature which man first admired and then endeavoured to imitate.

Some of the palms and other endogenÆ are of a most beautiful form, and are moreover quite as useful as beautiful, furnishing food to the inhabitants of many regions, especially the Arabs of the Desert, who carry the dried fruit of the Date-palm with them, on crossing these vast plains of sand, as their chief food. The Plantain (Musa sapientum) forms a most beautiful and graceful object, with its enormous leaves springing up from the ground by their midrib in clusters, and extending upwards for 20 or more feet in graceful curves, affording a shady and cool retreat beneath them from the burning rays of the sun; the fruit is also one of the necessaries of life in the regions where they abound. The Fan-palm is another beautiful specimen, from the fan-like leaves of which the punkahs or Indian fans are made. The Palmyra palm furnishes leaves which are used to thatch houses, the sap is drunk as a refreshing beverage, and when evaporated yields a kind of sugar called "juggery," from which palm-wine is made.

The palms were amongst the first trees created, their fossil stems being constantly found; they were even then associated with the elephant and rhinoceros, and although these are found chiefly in the northern parts of Europe, yet it is much more reasonable to suppose that the climate of these parts has changed, than that these two favourites of the sunny regions should have had their natures changed.

Among the useful members of the endogenÆ may be mentioned the Maranta ArundinaceÆ, or Arrow-root plant, which is thus described by Dr. Baird:—"It is a genus of monocotyledonous plants, belonging to the natural order CannaceÆ or MarantaceÆ, and composed of herbs which have a well-developed rhizome or tuberous root containing a large quantity of fecula or starch. The species are natives for the most part, of tropical America, a few being also found in India. The structure of the flowers is remarkable, and the fruit fleshy. The most important species is the Maranta ArundinaceÆ, a plant which is extensively cultivated in the West Indies, the southern parts of the United States, and in the Isle of France, for the sake of its root, which affords the substance so well-known as Arrow-root. This root consists of a tuber of a peculiar form, and contains a large proportion of fecula; the stem is upwards of three feet high, and the flowers are white, delicate, and small. In Cayenne the tubers are eaten by the natives, roasted, as a cure for intermittent fevers, and when bruised, are applied by them to wounds, and considered more especially as a specific against those caused by poisoned arrows, hence the name of Arrow-root."

According to Dr. Livingstone, the inhabitants of Angola live almost exclusively upon the Tapioca plant. He thus describes the mode of preparing it, &c.:—"They (speaking of the half-caste Portuguese) subsist chiefly on the Manioc, and as that can be eaten either raw, roasted, or boiled, as it comes from the ground, or fermented in water and then roasted or dried after fermentation and baked, or pounded or rasped into meal and cooked as farina, or made into confectionery with butter and sugar, it does not so soon pall upon the palate as one might imagine when told that it constitutes their principal food. The leaves, boiled, make an excellent vegetable for the table, and when eaten by goats, their milk is much increased. The wood is a good fuel, and yields a large quantity of potash.... The root, rasped while raw, placed upon a cloth, and rubbed with the hands while water is poured upon it, parts with its starchy glutinous matter, and this, when it settles at the bottom of the vessel and the water is poured off, is placed in the sun till nearly dry to form tapioca, the process of drying is completed on an iron plate over a slow fire, the mass being stirred meanwhile with a stick; when dry, it appears agglutinated into little globules, and is in the form we see in the tapioca of commerce."

Although none of this family of plants produce building timber (according to our notions of that article), yet it is questionable whether we have a greater number of uses for our exogenous woods than are found by the natives of those countries where the EndogenÆ abound for palm stems and bamboo canes; as the Grecian styles of architecture arose from the imitation of structures of timber, so the Hindoo and Chinese styles have arisen from imitation of bamboo buildings. There is scarcely a constructive use that can be imagined to which this convenient material is not applied. In the "Penny CyclopÆdia" (article "Bambusa") is the following:—

"The purposes to which different species of bamboo are applied, are so numerous that it would be difficult to point out an object in which strength and elasticity are requisite, and for which lightness is no objection, to which the stems are not adapted in the countries where they grow. The young shoots of some species are cut when tender, and eaten like asparagus. The full-grown stems, while green, form elegant cases, exhaling a perpetual moisture, and capable of transporting fresh flowers for hundreds of miles; when ripe and hard, they are converted into bows, arrows, and quivers, lance-shafts, the masts of vessels, bed-posts, walking-sticks, the poles of palanquins, the floors and supporters of rustic bridges, and a variety of similar purposes. In a growing state the spiny kinds are formed into stockades, which are impenetrable to any but regular infantry aided by artillery.

"By notching their sides the Malays make wonderfully light scaling-ladders, which can be conveyed with facility where heavier machines could not be transported. Bruised and crushed in water, the leaves and stems form Chinese paper, the finer qualities of which only are improved by a mixture of raw cotton, and by more careful pounding.

"The leaves of a small species are the material used by the Chinese for the lining of their tea-chests. Cut into lengths and the partitions knocked out, they form durable water-pipes, or by a little contrivance are made into excellent cases for holding rolls of papers; slit into strips they afford a most durable material for weaving into mats, baskets, window-blinds, and even the sails of boats. Finally, the larger and thicker truncheons are exquisitely carved by the Chinese into beautiful ornaments. It is however more especially for building purposes that the bamboo is important (fig. 15). According to Marsden, in Sumatra the framework of the houses of the natives is chiefly composed of this material. In the floorings, whole stems four or five inches in diameter are laid close to each other, and across these laths of split bamboo about an inch wide are fastened down with filaments of rattan-cane. The sides of the houses are closed in with the bamboo opened and rendered flat by splitting or notching the circular joints on the outside, clipping away the corresponding divisions within and laying in the sun to dry pressed down with weights. Whole bamboos often form the upright timbers, and the house is generally roofed in with a thatch of narrow split bamboos six feet long, placed in regular layers, each reaching within two feet of the extremity of that beneath it, by which a treble covering is formed. Another and most ingenious roof is also formed, by cutting large straight bamboos of sufficient length to reach from the ridge to the eaves, then splitting them exactly in two, knocking out the partitions and arranging them in close order, with the hollow or inner sides uppermost; after which a second layer with the outer or convex sides up, is placed upon the other in such a manner that each of the convex falls into the two contiguous concave pieces, covering their edges, the latter serving as gutters to carry off the rain that falls upon the upper or convex layer."

The EndogenÆ are divided into twelve orders, as follows:—

1. GraminacÆ (Grasses).

The GraminacÆ comprise the great bulk of those plants which supply man and the lower animals with food, for it contains all the grasses and corn-bearing plants, including rice, maize, wheat, oats, barley, and rye. Upon these all the Ruminants of the earth feed, and millions of human beings taste no other kind of food. There are nearly 4000 species of graminaceous plants, rice and maize being the most broadly extended, forming the chief food of the Chinese, Hindoos, and other nations; wheat is here the most valuable grain, and is now grown in all parts of Europe and America. Humboldt, in his "Views of Nature," gives an interesting account of the first wheat grown in New Spain. He says:—

"A negro slave of the great Cortes was the first who cultivated wheat in New Spain, from three seeds which he found in some rice brought from Spain for the use of the troops. In the Franciscan convent of Quito I saw, preserved as a relic, the earthen vessel which had contained the first wheat sown in Quito by the Franciscan monk Fra Jodoco Rixi de Gante, a native of Ghent in Flanders. The first crop was raised in front of the convent, on the Plazuela di San Francisco, after the wood which then extended from the foot of the volcano of Pinchincha had been cleared. The monks, whom I frequently visited at Quito, begged me to explain the inscription, which, according to their conjecture, contained some hidden allusion to wheat. On examining the vessel, I read in old German the words,

"'Let him who drinks from me ne'er forget his God.'

"This old German drinking-cup excited in me feelings of veneration. Would that everywhere on the New Continent the names of those were preserved who, instead of devastating the soil by bloody conquests, confided to it the first fruits of Ceres."

The third great natural family of plants are the ExogenÆ. They comprise all the trees and shrubs of the temperate and colder regions, together with many of the flowering plants. They are characterised by certain peculiarities which can be at once recognised, such as the twisted and branched form of the stem, the possession of bark, leaves having the veins covering them running in all directions and forming a network, and the seeds containing two cotyledons; the wood, moreover, is deposited in rings (figs. 16, 17, 18, 19), one of which is formed every year, by the new wood being produced on the outside of the old, and between it and the bark. This deposition takes place as follows: after the rains of winter and early spring have well saturated the earth with moisture, and the warmth of spring has begun to penetrate to the roots of the plants, a development of the points of each fibrile or radicle takes place, forming new spongioles; these, being formed of new porous cellular tissue, begin to absorb (by endosmose) the moisture of the earth, which entering at all these thousands of minute spongioles at once, collects and rises in the vessels of the trunk and branches, and arriving at the vessels forming a plexis on the surface of every leaf, begins to be changed by the action of the sun's rays, absorbing carbon and giving out oxygen from the carbonic acid always contained in the air. The sap which has thus risen is the juice of the earth in which the plant grows, containing several earthy salts and vegetable extract drawn from the manure or decaying vegetation contained in the mould, together with carbonic acid dissolved in the fluid; this carbonic acid is changed by the sun's rays as well as that which was contained in the air, and the carbon uniting with the watery part of the sap, forms the green substance before alluded to, called chlorophyll, which is the green colouring matter of all plants, and is the basis of the wood. The altered sap descends between the wood and the bark, and forms a deposit gradually, which at the end of the year is a complete ring of wood surrounding the wood of former years. This circulation of juices continues through the summer, until, the cold weather coming on and the light being diminished, the sap neither rises nor is the leaf nourished by it, when it decays and falls off.

The age of exogenous wood can be ascertained—where the centre has not decayed—by counting the rings, one only being deposited every year; and it is truly astonishing to find that some trees will continue to live and flourish for several thousand years! There does not, in truth, appear to be any limit assigned to the life of an exogenous tree if it escape accidents; for, although decay inevitably attacks the heartwood, and a cavity is the result, yet, the new wood continuing to be deposited on the outer part, the vitality of the tree is kept up, and its size continues to increase.

The Baobab or Monkey Bread-fruit trees, growing at the mouths of the Senegal, have been estimated by Adinson to be upwards of six thousand years old, and are, in all probability, the oldest relics of organic life existing at the present time. The cedars of Lebanon are supposed to have existed longer than the records of history. The Yew at Braburn, in Kent, is at least three thousand years old; and that of Fortingal nearly as much.

Dr. Livingstone, describing the Mowana or Baobab tree (fig. 20), thus comments upon its power of withstanding injury:—

"No external injury, not even a fire, can destroy this tree from without, nor can any injury be done from within, as it is quite common to find it hollow, and I have seen one in which twenty or thirty men could lie down and sleep as in a hut. Nor does cutting down exterminate it, for I saw instances in Angola in which it continued to grow in length, after it was lying on the ground. Those trees, called exogenous, grow by means of successive layers on the outside; the inside may be dead, or even removed altogether, without affecting the life of the tree; this is the case with most of the trees of our climate. The other class is called endogenous, and increases by layers applied to the inside, and when the hollow of the tree is full, the growth is stopped, and the tree must die. Any injury is felt most severely by the first class on the bark, by the second on the inside, while the inside of the exogenous may be removed, or the outside of the endogenous may be cut, without stopping the growth in the least. The Mowana possesses the power of both. The reason is, that each of the laminÆ possesses its own independent vitality; in fact, the Baobab is rather a gigantic bulb run up to seed than a tree. The roots, which may often be observed extending along the surface of the ground forty or fifty yards from the trunk, also retain their vitality after the tree is laid low, and the Portuguese now know that the best way to treat them is to let them alone, for they occupy much more room when cut down than when growing."

On examining the wood of the exogenÆ, it will be found that in the very centre is a small column of cellular tissue, called the pith, and that from this, fine layers of the same substance radiate towards the circumference. These are called the medullary rays, or silver-grain; they form an exterior layer or ring of cellular substance on the outside of the wood, which is called the cambium. The lightness of wood is owing to its porosity, and, on examining a transverse section under the microscope (figs. 17 and 19), it will be seen how little of real space is occupied in wood by solid substance. The spaces between the wall-work of woody matter in the tree are all filled with sap, and hence it is that "green wood" is so much heavier than that which is well seasoned. It is its lightness and strength, together with the ease with which it can be cut and fashioned, which renders wood so exceedingly useful; but its inflammability and liability to decay are great barriers to its more general use.

The leaves of the exogenÆ have their veins always in the form of a network, and not running parallel with each other, as in the endogenÆ (fig. 21).

Of the three divisions of the vegetable kingdom, the exogenÆ alone furnish building timber, properly so called, and it is doubtful whether nature has supplied a more generally applicable substance than wood; being a bad conductor, it can be handled in the coldest weather, which metal cannot, and, being easily cut or split, can be fashioned into almost any form.

The woods mostly in use for general purposes are the different kinds of pine, as American Pine, Norway Pine, yellow and white Deal, Mahogany, Oak, Beech, Elm, Ash, and Maple. In the "Penny CyclopÆdia," under the article "Wood," is the following description of the different kinds used by cabinet-makers, &c.:—

"The woods that are used by the cabinet-maker for furniture of a more delicate kind are called 'fancy woods.' The use of these has become much more general since the introduction of the art of veneering, and now that this is done by machinery instead of by hand, a number of woods are used for furniture and other purposes, which, on account of their scarcity, could have been formerly used only to a very limited extent. The most common of the fancy woods, and that which is most used by cabinet-makers, is Mahogany. This wood is the produce of the 'Swienteria Mahogani.'

"Next in point of importance and use to Mahogany, is Rosewood. This wood obtains its name from its fragrance, and is the produce of a mimosa from the forests of Brazil; in veneering it affords about eight plates to the inch.

"King-wood is a beautiful wood much in use, brought from Brazil in logs four feet long and about five inches wide, and is used only for delicate articles; it is said to be the produce of a species of Baphia, a genus of Leguminous plants.

"Beef-wood is a very heavy wood of a pale red colour, and is brought from New Holland in logs nine feet long and thirteen or fourteen inches wide; the tree from which this is obtained is unknown to botanists, as well as most of those producing the fancy woods of commerce.

"Tulip-wood is brought into the market in very small pieces, not more than four feet long and five inches in diameter, so that probably it is the production of a shrub; it is clouded with red and yellow colours, and is used for bordering and for making small articles, such as caddies and work-boxes.

"Zebra-wood is probably the production of a large tree, as it is cheap enough to be made into tables, pianofortes, &c.; it is coloured brown on a white ground and clouded with black.

"Satin-wood is of a brilliant yellow colour with delicate glowing shades. It is the produce of a plant called Chloroxylon Swienteria, a native of India; it is one of the trees that yield the wood-oil of India, and belongs to the natural order CedrelaceÆ, the same order in which the mahogany is placed; it is found in the market in logs two feet wide and seven or eight feet long.

"Sandal-wood is the produce of a species of Sandoricum belonging to the family MeliaceÆ; the wood is of a light brown colour with golden-coloured waves.

"Ebony and Iron-wood are the names given to some very hard woods, the produce of the natural order EbenaceÆ. These woods are mostly brought from India, although some of the species are found in Europe and America.

"There are several other woods occasionally used amongst cabinet-makers, of which little is known, either with regard to the places they come from, or the trees to which they belong. Canary-wood has a yellow colour; Purple-wood has a purple colour, without veins; Snake-wood is of a deep colour with black shades; Calander-wood is a handsome cheap wood taking a high polish, and is brought from Ceylon.

"Other woods are named after the places they come from, as Coromandel-wood, Amboyna-wood, &c."

Woods are largely used as dye-stuffs; the chief of these is log-wood, which has a deep red colour, is very heavy and solid, and yields a great deal of red colouring matter. It is very astringent, and contains tannic and gallic acids, from which properties it produces a deep black colour when mixed with any of the salts of iron; from this peculiarity it is very valuable as a black dye, but the black dye so extensively used for dyeing cloth, is, for the most part, made from galls, or "nut-galls," as they are sometimes called. These are hard round substances found growing on many species of oak, chiefly the "Quercus infectoria," and the best are brought from Aleppo; they are diseased growths produced by a little insect, called the "Cynips Quercus," which deposits its eggs under the epidermis of the leaf, and the juice collects and forms the gall (fig. 22), from the interior of which the larva eats its way out; thus it will be found that every gall must have a little round hole in it, whence the larva of the cynips has issued.

The root of the Madder plant (Rubia tinctorum) produces the most beautiful and permanent of our red dyes, and the cochineal insect (Coccus cacti) obtains its colour from feeding upon the cactus.

A useful and very permanent blue dye is obtained from Indigo, a kind of extract from the plant "Indigofera," growing in India and other places, and many other members of the vegetable kingdom yield dyes and colours used in the arts.

Amongst the various and almost endless purposes to which wood is applied, that of serving as a material to engrave on and print from must not be omitted. The wood used for this purpose is that of the box-tree (Buxus sempervirens), which furnishes a close, even-grained, hard wood, admirably suited to the purpose; and the cultivation and perfecting of this most admirable art, has produced an improvement in book-illustrating which can hardly be sufficiently appreciated.

Wood must have supplied one of the earliest materials with which to erect buildings; the Grecian styles of architecture, beyond doubt, were derived from imitating in stone those structures first made of wood. All the largest members of the vegetable kingdom belong to this division; and indeed the same may be said of size which has been said of age, namely, that there is no limit except from accidental circumstances.

In the Crystal Palace at Sydenham is a most wonderful and gigantic specimen of the Wellingtonia Gigantea (fig. 23), one of the class of trees called coniferous, and belonging to the exogens, the bark of which has been stripped off in portions at the place where it grew, each of which being numbered, has enabled them to be re-adjusted in their original places, the result of which is, the whole bark of this most magnificent tree appears as if growing on the timber. It measures 31 feet across at the base, and 93 feet in circumference; the original tree was 363 feet in height, its present height is 116 feet, and the bark is 18 inches thick. The Norfolk Island Pine (Araucaria excelsa) sometimes grows to 300 feet in height, and Humboldt, describing a specimen of the Pinus Trigona, says, "This gigantic fir was measured with great care; the girth of the stem at 6-1/4 feet above the ground was often 38 to 45 feet; one stem was 300 feet high, and without branches for the first 192 feet."

As the exogens grow by the addition of woody matter to their circumference, of course the older the tree (other conditions being equal) the larger will be the trunk, but as the new wood is added to the outside, the centre loses its vitality and is liable to the attacks of both animal and vegetable parasites, and is therefore constantly found either decayed or totally destoyed; this is not, however, invariably the case, and many instances are found of wood of a great age remaining sound in the centre. At St. Nicholas in Lorraine is exhibited a plank of walnut wood made into a dining-table which is twenty-five feet wide. Besides timber for various useful purposes, this division of the vegetable kingdom furnishes us with both cotton and linen for clothing, and many of the dye-stuffs for ornamenting such clothing, also with many articles of food (although not so prolific in this respect as the EndogenÆ), the potato, most green vegetables, as cabbages, lettuces, are exogenous, together with such roots as carrots, parsnips, &c.

To this class of plants belong many of the most beautiful flowers, and all our fruit-trees, not the least important of which is the fig-tree, although the fig can hardly be called a fruit in the strict sense of the word, being a consolidated mass of flowers within a receptacle. The figs of commerce are produced from the Ficus carica, the fruit being dried in the sun; they form a considerable article of commerce. The celebrated Banyan tree (Ficus indica, fig. 24) is one of the fig tribe, it throws down branches (as do many others of this tribe) which take root in the earth and form fresh stems, so that one of the banyan trees with its off-shoots will cover a space of ground sufficient to shelter a regiment of cavalry, and many of the fig tribe, especially the sycamore (Ficus sycamorus), are planted for the sake of the shelter they supply by their broad crowns of leaves; another of the fig trees (Ficus elastica) supplies a great part of the India-rubber of commerce.

De Candolle divides the class of exogens into four sub-classes according to the arrangement of their flowers &c.; they are as follows:—

1. ThalamiflorÆ, the flowers of which are furnished with both calyx and corolla, the corolla having distinct petals, and the stamens hypogynous, that is, growing immediately from below the pistil.

2. CalyciflorÆ, having flowers with both calyx and corolla, the corolla divided into distinct petals, but the stamens always Perigynous, that is, growing upon the sides of the calyx.

3. CorolliflorÆ, having flowers with both corolla and calyx, the former having its petals united.

4. MonochlamydeÆ, flowers without corolla and often without a calyx.

These four sub-classes have been divided into orders as follows:—

Orders of ThalamiflorÆ.

1. NymphaceÆ (NymphÆa alba) White Water-Lily.
(Nuphar luteum) Yellow Water-Lily.

This order contains water plants of great beauty, they grow in the mud at the bottom of the water, sending up long flower- and leaf-stalks so that the flowers may blossom in the air and the leaves float on the surface; the leaves are generally round and turned up slightly at the edges. The "Victoria Regia" is a magnificent specimen of this order; it originally came from Brazil, and has flowers a foot wide, leaves four or five feet across, and is sufficiently buoyant, it is said, to bear the weight of a child. The Lotus of the Nile, the blossom of which so frequently occurs on the carvings of the Egyptians as an offering to Isis, is another member of this order.

2. PapaveraceÆ (Papaver somniferum) White Poppy.
(Papaver Rhoeas) Red Poppy.

Opium is prepared from the unripe capsules of the White Poppy, it is chiefly cultivated for this purpose in India and Turkey. The Chinese are the great consumers of opium, it being a common habit with them both to eat and smoke it. Opium is made by collecting the juice in the morning which has exuded from incisions made in the capsules over night; those employed for this purpose use a small knife with several blades and go round the plantations scarifying the capsules in the evening, and the juice which issues and forms a thick concrete matter, is scraped off, beaten up, and dried in round lumps. About £2,000,000 worth are exported from India annually.

14. MalvaceÆ (Malva sylvestris) Common Mallow.
(AlthÆa officinalis) Marsh Mallow.

The Marsh Mallow has been much esteemed as a demulcent medicine, and an ointment is made from it for external use; but one species of this order, the Gossypium, is one of the most important plants in the whole world, producing that most useful article, cotton, so largely grown in America, and for which the slave population are chiefly employed. The fine white hairs surrounding the seeds and filling up the pod is the part picked out and preserved, it forms the cotton-wool of commerce, of which some eight hundred millions of pounds' weight are used annually! employing a million and a half people, in England alone, and furnishing clothing to hundreds of millions. It is grown in India, which is supposed to be its native place, and will probably be grown to a much greater extent when railways and canals shall have made a more easy communication from the interior of that country to the sea-board.

16. LinaceÆ (Linum usitatissimum) Common Flax.

The Flax plant is another of those insignificant plants which, from certain properties they possess, have become the greatest boons to mankind; the stalks of the Linum usitatissimum, soaked, bruised, and prepared by combing, &c., form the flax of commerce, from which all our linen fabrics are made. The manufacture of flax is one of the oldest arts known, the ancient Egyptians formed their mummy-cloths from this article, and a piece of one of these cloths, bleached and placed side by side with some of the present date, would hardly suffer by the comparison, but the rapidity of its manufacture, and the price at which supplied, are doubtless very different in the two cases.

The value of the linen manufacture of Great Britain is between seven and eight millions yearly.

The seeds of the flax plant (Linseed) are used to crush and produce the linseed oil of commerce so extensively used in the production of paints and varnishes, and the cake is used as food for cattle.

This completes the orders of ThalamiflorÆ, which, with the following sub-class, CalyciflorÆ, contain all our star-like flowers, or those in which the corolla forms a whorl or open ring of petals. The third sub-class contains those chiefly in which the flowers form cups or bells.

Orders of CalyciflorÆ.

4. RosaceÆ (Rosa centifolia) Hundred-leaved Rose.
(Fragaria vesca) Wood Strawberry.
(Rubus fruticosus) Bramble.
(Pyrus communis) Pear Tree.

This important order yields us our most beautiful flower, the Rose, of which there are a great many varieties, among which the Dog-rose—that beautiful ornament to our hedges—deserves to hold a conspicuous place, also the Sweetbriar or Eglantine. The rose is used in Turkey and Persia for obtaining that most valuable and delicious perfume, "Otto of Roses." It is made by distilling a portion of water from several quantities of fresh roses, until it becomes saturated with the volatile oil. This water is then exposed to the open air, and, in the cool night time, drops of the otto collect on the top, from which it is carefully gathered, and the same water again distilled from a fresh quantity of roses. Besides the Rose tribe, this order contains some of our most valued fruits. The Apple, Pear, and Strawberry belong to it, also the Almond.

Orders of CorolliflorÆ.

15. SolanaceÆ (Atropa belladonna) Deadly Nightshade.
(Solanum tuberosum) Potato.
(Capsicum annuum) Capsicum.
(Hyoscyamus niger) Henbane.
(Nicotiana Tabacum) Tobacco.

A great many members of this order are poisonous, among which the Deadly Nightshade (Atropa Belladonna) is the most virulent, there are also Henbane and Tobacco, both strong poisons; but, to compensate for this bad character, the order contains one of the most useful vegetables used in Europe—the Potato. This is the tuber of the "Solanum tuberosum." The following account of the introduction of the Potato into England is from the "Penny CyclopÆdia":—

"Queen Elizabeth, in 1584, granted a patent 'for planting and discovering in new countries, not possessed by Christians,' and, under this sanction, some ships, principally equipped by Sir Walter Raleigh, sailed with him to America. Thomas Harriott (afterwards known as a mathematician) who accompanied the adventurous squadron, transmitted to England the description of a plant, called Openawk by the natives of that part of America, which the courtier-like gallantry of Raleigh had named 'Virginia.' Harriott described the Openawk as having the roots round, and 'hanging together as if fixed on ropes, and good for food either boiled or roasted.' Girarde in his Herbal a few years subsequently, distinguished the plant by a plate, and not only confirmed the assertion that it was an indigenous production of Virginia, whence he himself had obtained it, but supplied some curious details of its qualities, and of the various modes in which it might be dressed for the table. But the Potatoe had been known in Spain and Portugal at an earlier period, and it is from the latter country that we most directly derive the name by which we know it. This is easily shown; although the natives of South America called the plant by the name 'Openawk,' those of the South, more particularly the inhabitants of the mountains of Quito, called it 'Papas,' which the Spaniards corrupted into 'Battata,' this again their neighbours in Portugal softened into 'Ba-ta-ta' (da terra), to which 'potato' is a very close approximation."

This plant, the tubers of which for a long time were a luxury obtainable by the rich only, now yields the support of the poor, and furnishes the cheapest food known; the peasantry of Ireland almost subsist upon Potatoes, and the poor of most parts of Europe find it indispensable to their living.

Orders of MonochlamydeÆ.

6. CorylaceÆ (Castanea vesca) Sweet Chestnut.
(Quercus pedunculata) Oak.
(Corylus avellana) Hazel Nut.

This order contains some of our finest trees; the Oak, that prince of trees, is of this order. It attains a great age and size, and there are some celebrated specimens existing which have stood many centuries. Oaks constitute the greater part of the forest trees, both on the Continent and in England; great numbers are cut in France for fire-wood, and in both countries for ship-building. The roof-timbers of our old churches and halls are nearly all oak. The bark of the oak is largely used for tanning leather. About 30,000 tons are imported into this country yearly for this purpose, besides the product of our own trees. The bark of the Cork-oak (Quercus suber) is used for making corks, some 2,000 tons of this are imported annually. Moreover, the Gall-nut used in tanning, and also to make black dye, is the product of an oak. The Chestnut is a fine tree, the nuts of which are commonly eaten by the peasantry of Spain and Italy as food; the tree grows to a great age and to an enormous size.

It is from the vegetable kingdom that most of the medicines in use are derived, but many of these, in improper doses, act as violent poisons; indeed, the most rapidly fatal of all poisons, prussic acid, was originally distilled from the Laurel-cherry, and strychnine, which is hardly less rapid, is the produce of the Nux vomica (Strychnos nux vomica).

The following is a list of the principal poisonous plants found growing wild in England:—

Those marked (*) in the foregoing list are acrid poisons, and the remainder are narcotic.

Out of these three great families of plants, in their almost endless variety of size, form, and colour, it has pleased the Great Author of Nature to form all the vegetation which beautifies this earth, from the lofty Palm—which, from its grateful freshness and the beauty of its structure, seems almost as if possessed of more than vegetative life, to the AlgÆ, which form "the pool's green mantle"—from the gigantic and "storm-defying" Oak, with its green foliage spreading out far above, and throwing its welcome shade around, to defend from the sun's rays the gentle deer who pasture on the herbage beneath—to the grass and clover, and the sweet-smelling wild flowers at their feet—

form inexhaustible themes on which to exercise our faculties of admiration, and which serve admirably to minister to those wants which, without doubt, were given to us that we might derive pleasure from their being thus beautifully gratified—themes for the pencil of the artist, who "holds, as it were, the mirror up to nature," and the architect, when he designed his vistas of slender columns spreading out into and supporting roofs of tracery, might well be supposed to have had in his "mind's eye" some beautiful recollection of the arcades of Nature's palaces in the sombre forests, where the twisted trunks of the trees, the fretwork of their branches, and the leafy covering formed by their leaves, supply all the requisites of a grand and lofty temple, fit for the worship of that great First Cause who formed them.