Fig. 87.—The Beech(Fagus).
Fig. 87.—The Beech(Fagus).
TheBeech (Fagus sylvatica) bears very little resemblance to the Oak. The male flowers are in globular catkins (seeainfig.87), each flower consisting of a bell-shaped calyx (b), cleft into five or six teeth, and containing eight orten stamens, which project beyond it. The female flowers also grow in globular heads (c) two or three together, surrounded by a great number of linear bracts, which gradually grow together, and form a four-lobed involucre shown open atd. In the centre of this involucre are two or more female flowers, each surrounded bya hairy calyx, cut into teeth at the tip (e). Each flower has three styles (f); and the ovary, which is sharply angular, has three cells, with two ovules in each. As the fruit swells, the linear bracts diminish, till at last they have only the appearance of small spines on the involucre (g), which opens when ripe into four valves (h), and contains two or three angular nuts (i), which are called the mast. The leaves of the Beech are of thin and delicate texture, and they are strongly feather-nerved. The tree is large and very handsome, and it is easily known, even in winter, by the smooth shining white bark of the main trunk. There are only two species of Fagus common in British gardens, and these are the common Beech (Fagus sylvatica) which has numerous varieties, including one with dark reddish purple leaves, generally called the Purple Beech; and the American Beech (F. ferruginea), the leaves of which are copper-coloured.
There are, however, two species from Terra del Fuego, which have been introduced, but they are at present rare. One of these (F. betuloides) is called the Myrtle tree in Van Dieman’s Land, where it is also found wild, and it is remarkable for producing a fungus on its trunk, which, when cut in slices and cooked, is said to be very good to eat.
THE GENUS CASTANEA.
Fig. 89.—Fruit of the Sweet Chestnut.
Fig. 89.—Fruit of the Sweet Chestnut.
Thisis a very small genus, only containing two or three species, of which only one, the Sweet Chestnut (Castanea vesca) is common in England. This plant was included by Linnæus in the genus Fagus, but it appears very distinct. The male flowers are produced round a central axis, but so far apart as hardly to be like aFig. 88.—Chestnut(Castanea vesca).catkin (seeainfig.88). These flowers in the bud look like little knobs, but when they open the stamens burst out, as shown atb. Each flower has a large and a small bract, and from ten to fifteen stamens. The female flowers are disposed in a tuft as shown atc, surrounded by a number of bracts and scales, which afterwards grow together and form a spiny involucre (seefig.89a,) which forms the husk of the ripe nuts (b), and opens into four valves as shown atc. Each female flower has a closely-fitting calyx, toothed at the tip, which afterwards becomes the hard brown skin that envelops the kernel of the ripe nut; andeach flower is furnished with six styles, having as many cells with two ovules in each, though generally all the cells unite into one, and most of the ovules wither before the fruit ripens. There are three female flowers in each involucre, which lie nestling together like birds in a nest. When ripe the involucre or husk opens naturally into four valves (as shown infig.89), and drops the one or two Chestnuts which it contains. Each nut, when ripe, is enveloped in a brittle shining skin formed of the metamorphosed calyx, and consists of only one cell, in which are one, two, or at most three kernels, which are the seeds.
THE GENUS CORYLUS.
TheHazel Nut (Corylus Avellana) has the male and female flowers on the same tree; the male being in long catkins and the female ones in little oval buds, something like those of the Oak, (seeainfig.90,) which are so small that they would hardly be seen on the tree, if it were not for their bright red stigmas. TheFig. 90.—The Hazel(Corylus Avellana.)male flowers (fig.91) have each three bracts, one behind the two others, to the inner ones of which are attached eight stamens. As the buds containing the female flowers expand, two or three small leaves make their appearance between the scales (binfig.90), soFig. 91.—Male flower of the Hazel.that gradually the bud becomes a little branch, bearing the female flowers at its tip. Each flower has two long stigmas, and the ovary is enclosed in a closely-fitting calyx (c) toothed at the upper part, the whole being enveloped in a deeply cut involucre (d), which afterwards becomes the husk of the ripe nut. This involucre is not closed, as in Fagus and Castanea, but it is open at top; the nut, as in all cupuliferæ, adhering to it, when young, by the hilum or scar visible at its base. There are about seven species of Corylus, of which the most remarkable is the Constantinople Nut (Corylus Colurna.) The Filbert is only a variety ofCorylus Avellana.
THE GENUS CARPINUS.
Somebotanists include this genus and that of Ostrya in the order Betulaceæ, instead of placing them in Cupuliferæ, as the nut of the Hornbeam is not surrounded by a cup or husk, but by a leaf-like involucre as shown infig.92,Fig. 92.—Fruit of the Hornbeam.ata,bbeing the nut. Both the male and the female flowers are produced in long catkins, which have an exceedingly light and elegant appearance on the tree. The male flowers consist each of one bract, with twelve or more stamens attached to its base; and the female flowers have each two very long stigmas, and a ribbed calyx, which adheres to the ripe nut and assumes the appearance of a hard brown skin. The leaves are feather-nerved and persistent, like those of theBeech, frequently remaining on the tree, though in a withered state, till spring.
The nut appears ribbed when ripe, from the remains of the metamorphosed calyx, and it contains only one seed; though, as in the other allied genera, the ovary had two cells, with an ovule in each.
THE GENUS OSTRYA.
TheHop Hornbeam (Ostrya vulgaris) was included in the genus Carpinus by Linnæus; and indeed the general construction of the flowers is the same. The male catkins are, however, very much longer, and the female catkins much shorter, and closely resembling those of the Hop.
THE ORDER PLATANACEÆ.
Thisorder formerly included the Plane trees and the Liquidambar; but many botanists now put the latter tree in a separate order, which they call Balsamaceæ.
THE GENUS PLATANUS.
Inthe Oriental Plane (Platanus orientalis) the male and female flowers are both in globular catkins. The male flowers are composed of very small, but rather fleshy bracts, which remain on after the stamens fall; and the female flowersare each furnished with bracts, and have two long stigmas. Both kinds of flowers are so small as not to be seen without a microscope. The fruit is covered with fine hair. The globular catkins retain the bracts, and these remain on after the seed has fallen, giving the tree a very singular appearance even in winter. The Occidental Plane (P. occidentalis) differs principally from the preceding species in the leaves being more downy beneath; the buds are also so downy that the tree in America is called the Cotton-tree. Both kinds are remarkable for the manner in which the bark becomes detached from the main trunk and peels off.
THE GENUS LIQUIDAMBAR.
Thecommon Liquidambar (L. styraciflua) is remarkable for the beautiful crimson which its maple-like leaves take in autumn. The male flowers are on an upright catkin, and the female ones in a globular one, like the Planes. When the fruit is ripe, the numerous capsules that surround the globular catkin burst, and the seeds, which are winged, are scattered by the wind.
THE ORDER MYRICACEÆ.
Theprincipal genera are Myrica, the Sweet Gale; Comptonia, a curious shrub with fernlike leaves; and Casuarineæ, a New Holland tree without leaves, but with jointed leaf-like stems.
THE GENUS MYRICA.
Themale flowers are produced in rather long erect catkins, each having only one scale, and four stamens. The female catkins are short, and each flower has three scales or bracts; the ovary has two long stigmas, and the fruit is a drupe, the scales becoming fleshy when ripe. The bracts and leaves are covered with glands filled with aromatic oil; and inM. cerifera, the fruit is covered with a waxy secretion, which is used as wax.
THE ORDER GARRYACEÆ.
Thisorder consists of only one genus, Garrya.
THE GENUS GARRYA.
Garrya ellipticais an evergreen shrub remarkable for its long and graceful male catkins, the flowers of which consist of four stamens within a four-cleft calyx, enclosed within bracts united at the base. The female flowers are on a different plant, and the fruit is a berry not opening naturally.
THE CONE-BEARING TREES: ILLUSTRATED BY THE SCOTCH PINE; THE SPRUCE FIR; THE SILVER FIR; THE LARCH; THE CEDAR; THE ARAUCARIA; THE ARBOR VITÆ; THE CYPRESS; THE DECIDUOUS CYPRESS; THE JUNIPER; THE YEW; AND THE CYCADEÆ.
Thegreater part of the trees included in this chapter are comprised by Richard, De Candolle, and other foreign botanists, in the order Coniferæ; which they have divided into three sections: viz., the Abietineæ, or Pine and Fir tribe; the Cupressineæ, or Cypress tribe; and the Taxineæ, or Yew tribe. The last tribe, however, Dr. Lindley has formed into a separate order, which will probably be adopted. Most of the genera have, what the Germans so graphically call needle leaves; that is, their leaves are long and narrow, and terminate in a sharp point. The flowers also are quite different from what is generally understood by that name; being in fact nothing but scales: those of the male flowers containing the pollen in the body of the scale, and those of the female producing the ovules, or incipient seeds at the base. The fruit of the Abietineæ is a cone, the scales ofwhich open when the seeds are ripe. That of the Cupressineæ is also called a cone by botanists, but it is rounder, and has not so many scales. The fruit of the Taxineæ is an open succulent cup, bearing the seed or nut in its centre.
Linnæus placed nearly all the hardy Abietineæ in the genus Pinus, and since his time botanists have disagreed exceedingly respecting the generic names of the different plants; no less than twelve different divisions of them having been published, by as many eminent botanists, since the commencement of the present century. The best, however, appears to be that of M. Richard, which was approved by De Candolle, and which has been adopted with a slight alteration in Mr. Loudon’sArboretum Britannicum.According to this arrangement, the hardy Abietineæ are divided into five genera; viz., Pinus, the Pine, including all the resinous trees with long leaves, which grow two or more together in a sheath; Abies, the Spruce Fir, the leaves of which do not grow in a sheath, but are scattered round the branches, the leaves themselves being short, flat, and the same on both sides; Picea, the Silver Fir, the leaves of which resemble those of Abies, except that the edges curl in, and the under surface is quite different from the upper one, being marked with two white lines, one on each side the midrib; theleaves are also placed nearly in two rows, one on each side the branch; Larix, the Larch, the leaves of which are very slender and produced in tufts, but which fall off every winter; and Cedrus, the Cedar, the leaves of which resemble those of the Larch, but which do not fall off every winter. The distinctions between these genera in the leaves only are very clear, and easily remembered; and their cones differ as decidedly: those of the Pines are hard and thick at the tips of the scales, which remain on after the seed drops; those of the Spruce Firs are thin at the tips of the scales, which also remain on the cones after they have lost their seeds, and the cones are drooping, and tapering at both ends; those of the Silver Firs are erect, cylindrical, and of nearly the same diameter throughout, and the scales fall with the seeds; those of the Larch are erect, but small and conical, and the scales remain on after the seeds have fallen; and those of the Cedar are erect, oval, and with deciduous scales. To the hardy genera may now be added Araucaria, as one species of this genus (A. imbricata) has been found quite hardy in Britain.
The Cupressineæ are divided into four or five genera; viz.,Thuja, the Arbor Vitæ, some of the species of which have been formed into a new genus under the name of Callitris;Cupressus,the Cypress;Taxodium, orSchubertia, the deciduous Cypress; andJuniperus, the Juniper. The only needle-leaved trees belonging to Taxineæ belong to the genus Taxus, the Yew, unless we separate from it the new genus Torryea.
§ 1. THE ABIETINEÆ.—THE PINE AND FIR TRIBE.
Theplants included in this section, with the exception of the Larch, are evergreens. They are all lofty trees, with straight erect stems, and their branches growing in whorls or tiers, so as to produce a very peculiar and striking effect. The male and female catkins are on the same plant; the female one containing two seeds at the base of each scale. The pollen of the male flowers is so abundant that any one passing through a grove of these trees in May or June, might fancy it was raining brimstone. Most of the species are timber trees, producing the wood called deal; that used for the flooring and other parts of houses, being principally the wood of the Scotch Pine, and the Norway Spruce. Most of the species produce turpentine, which is the thin part of the sap which flows from the tree when a notch is cut in the trunk; the thick part of the sap when purified by boiling is the yellow resin. Tar is produced by cutting the roots and wood of pine and firtrees into pieces, and putting them into a sort of oven; when the tar runs from the charred wood, and lamp-black is made from the soot which collects on the roof of the oven. Pitch is boiled tar. Pyroligneous acid is obtained by burning the wood into charcoal in an iron cylinder, and condensing the vapour that arises from it.
THE GENUS PINUS.
Fig. 94.—Cone of the Scotch Pine(Pinus sylvestris).
Fig. 94.—Cone of the Scotch Pine(Pinus sylvestris).
Thisgenus, according to Linnæus, was made to include all the Pines and Firs, the Cedar and the Larch; and this arrangement has been followed by the late A. B. Lambert, Esq., in hisFig. 93.—Branch of the Scotch Pine.magnificent work on this tribe. In its present restricted form, it contains only those plants that have long slender leaves, which are produced in membranaceous sheaths, (seeainfig.93) two, three, or five together. The male flowers are produced in long upright catkins, (m) growing two or three together, and they consist each of one scale, which is surmounted by a kind of crest, (b). The pollen is contained in two cells formed in the body of each scale, which open lengthways, as shown in the scale of the Scotch Pine (Pinus sylvestris), at (g) infig.94. The female scales or carpels when ripe form a strobile or cone (d), and in the Scotch Pine they are thickened at the tip (einfig.93); but when young they appear as shown at (f). Each scale is furnished with a thin membrane-like bract on the outside, which is conspicuous when young, but which is hidden by the scales in the ripe cone; and each has two seeds inside, which are each furnished with a long thin transparent wing (c). When the seed is ripe, the cone opens as shown at (d), and the seeds falling out are carried away by the wind. When theseed is sown and begins to germinate, the young plant sends down a root, and pushes through the ground its upright shoot, which has six cotyledons, bearing the husk of the seed upon their tip. All the species of the genus Pinus agree with the Scotch Pine in the construction of their flowers, and they differ from each other principally in their cones, and in the number of leaves which they have in a sheath. By far the greater number have two leaves in a sheath, (seeainfig.93,) and among these are the Scotch Pine (P. sylvestris), which has small straight cones without prickles;P. Banksiana, which has crooked cones;P. pungensand other American Pines, which have prickly cones, every scale being furnished with a sharp spine; the Corsican Pine (P. Laricio), and several allied species, which have no spines on their cones, but every scale curving outwards; the Pinaster (P. Pinaster) which has large cones, with very short broad spines, and the Stone Pine (P. Pinea), the cones of which are smooth and shining, and very large, and the seeds of which are eaten. The pines that have three leaves in a sheath, are chiefly natives of North America, and have prickly cones; such asPinus Tædaand its allies,P. ponderosa, remarkable for its heavy wood which sinks in water, and its large spreading branches; andP. SabniandP. macrocarpa, which have long,Fig. 95.—Weymouth Pine(P. strobus).slender, drooping leaves, and very large hooked cones. The pines which have five leaves in a sheath, include, among others, the Weymouth Pine (P. Strobus), the cones of which are long, narrow, and drooping (seefig.95);P. Lambertiana, which has cones above a foot long; andP. Cembra, which has an oval cone, the scales of which are concave, and the seeds without wings.
THE GENUS ABIES.—THE SPRUCE FIR.
Thisgenus includes all the Spruce Firs, and they are readily distinguished from the pines byFig. 96.—Spruce Fir(Abies excelsa).their drooping cones (seeainfig.96), the scales of which are not thickened at the tip, but drawn out into a thin brittle membrane; and their leaves, which do not grow erect in sheaths,but in rows standing out from the branches (b), and which being the same on both sides, look as if two had grown together to make one. The difference between the Pines and the Firs will be seen clearly by comparingfig.96, which represents a branch of the Spruce Fir, withfig.97, which represents a branch ofFig. 97.—Pinus pumilio.Pinus pumilio, a dwarf variety of the Scotch Pine.
The common Spruce Fir (Abies excelsa) is a tree of stately growth, with an erect pyramidal form, and numerous tiers of drooping branches. It is the loftiest of European trees, having been found in Norway 180 feet high. The crest of the male flower is larger than in the genus Pinus, as shown at (d)fig.98, in a magnified side view of one of the cells of a male scale (a), from which the pollen has been discharged, the empty case being shown at (c). The female scales (b) have each a small bract at the back, and two seeds inside, (e) the wings of which have each a little cavityat the lower part in which the seed lies, so that it is naked on one side, and clothed by the wing on the other. The Spruce Fir bears cones when the trees are of a very small size;Fig. 98.—The Spruce Fir(Abies excelsa).and these cones are very ornamental when young, being of a rich purple, while the male catkins are yellow tinged with red at the base. The sap from the Spruce Fir does not flow freely when the bark is wounded, as it does from the Scotch Pine; but oozes out gradually, and is what is called Burgundy pitch in the shops. Spruce-beer is made from the young shoots of the American Black Spruce. There are many species of Abies, but the most interesting areAbies Douglasii, a very handsome tree only lately introduced, of very quick growth; and the Hemlock Spruce (Abies canadensis). This genus is called Pinus by the Linnean botanists, Picea by Professor Link and some German botanists; and Dr. Lindley, who calls it Abies, includes in it the Silver Fir, the Larch, and the Cedar.
THE GENUS PICEA.—THE SILVER FIR.
Thisgenus, which includes all the Silver Firs, is readily distinguished from Abies by its leaves, which grow in two rows, one on each side the branch; thus the branch lies quite flat when placed on a table, or any other level surface. The leaves are also not the same on both sidesas in the Spruce Firs, but the under side is marked by two distinct lines of silvery white, one on each side the midrib. The cones stand erect, and the dorsal bract is frequently so large as to appear above the tips of the scales; and the scales themselves are deciduous, falling off when the seeds are ripe, leaving the central rachis bare. This last peculiarity is very striking; as both the Pines and Spruce Firs retain the scales of their cones after the seeds have fallen. The seeds of the Silver Firs are much larger than those of the Spruces; and they are not attached to the wing in the same manner. The Silver Fir is a noble tree, and takes its name from the epidermis of its bark; which in young trees is of a whitish grey, and smooth, though when the tree is about fifty or sixty years old, it cracks and peels off, leaving the dark brown rough bark beneath. The cones are produced two or more together; they are upright and cylindrical, being nearly as large at both ends as in the middle. The leaves all curve upwards at the point, thus showing conspicuously the white lines on the under side. A remarkable circumstance connected with this tree is, that when it is cut down, the stump will remain alive for many years, and even increase considerably in size, without producing any leaves or branches. One in the forests of theJura, which was ascertained to have lived ninety-two years after the tree had been cut down, had completely covered the section of the wood with bark. Strasburgh turpentine is produced from this tree. There are several species of this genus, some of which, as for example,Picea Webbiana, do not show the dorsal bract; while others, asP. nobilis, andP. bracteata, have it so large as to make the cone appear quite shaggy. All the species abound in resin, which frequently exudes from the cones. This genus is called Abies by Professor Link, and the German botanists.
THE GENUS LARIX.—THE LARCH.
Thisgenus consists of only three species, which are easily distinguished from the other Abietineæ by their losing their leaves every winter. The common Larch (Larix europæa) is a very handsome tree, with drooping branches, and foliage of a yellowish green, which dies off of a red tinge in autumn. The leaves are linear, and they are produced in tufts in a sort of woody sheath, some of them appearing in the same sheath with the female catkins. The male catkins are smaller, but appear in the same manner. The cones are small, and show the dorsal bracts when young, but when ripe they are seldom visible. The seeds are winged,and so very small, that it appears wonderful that a tree frequently above a hundred feet high can spring from them. The cones are of a bright red when young, but they become brown when ripe. The Larch grows very rapidly, and in situations where no other tree would thrive. Its wood is very valuable, and its bark is nearly as useful for tanning as that of the oak. The trees, however, in some situations are subject to a disease called pumping, by which the centre of the trunk becomes as hollow as though it were intended for a pump. The sap of the Larch produces the Venice turpentine; and in some parts of France a kind of gum, called the Manne de Briançon, which is used medicinally, is collected from the leaves.
THE GENUS CEDRUS.—THE CEDAR.
Thereare only two species in this genus, the Cedar of Lebanon (Cedrus Libani), and the Deodar (C. Deodara). The male catkins of the Cedar of Lebanon are produced singly, and each scale has a large crest. The cones are ovate, and the scales, which are very short and broad, fall with the seeds, in the same manner as those of the Silver Fir. The leaves resemble those of the Larch, but they are not deciduous. The male and female catkins are very often on different plants; and the trees attain a considerable age before they produce perfect seeds. The Cedar is remarkable for the enormous size of its branches, and for the shelf-like character they assume. The tree in a living state lasts several centuries, but the wood is of a very coarse grain and not at all durable; and though the resin appears so abundant in the cones as to ooze through the scales, there is so little in the trunk that it is never used for turpentine.
The Deodar Cedar (C. Deodara) closely resembles the common Cedar in its catkins and cones, but the foliage is of a beautiful glaucous green, and the leaves are so much longer as to give a peculiarly graceful character to the tree. The wood is remarkably durable, very fragrant, and of an extremely fine grain, taking so bright a polish, that a table which Mr. Lambert had of it in his drawing-room has been compared to a slab of brown agate. The trunk abounds in resin, and it produces in India a great quantity of fluid turpentine, which though it is of rather a coarse quality, is much used by the natives; pitch and tar are also produced by charring the wood. The tree on the Himalayas grows above 150 feet high, with a trunk 30 feet or more in circumference, and it is said to live to a great age. It was only introduced into Britain in 1822, but there are numerous specimens of it in different parts of the kingdom, all of which appear quite hardy.
THE GENUS ARAUCARIA.
Araucaria imbricata, the only hardy species, is a very singular tree. The trunk is quite straight, with a strong leading shoot, and whorls of branches of great length, and far apart from each other, covered closely with scale-like leaves. These large horizontal arms, clothed with closely imbricated leaves, resemble, in the young trees, snakes partly coiled round the trunk, and stretching out their long, slender, flexible bodies in quest of prey. The male and female flowers are on different trees. The male catkins are cone-shaped, the scales serving as filaments to the anthers produced at their base. The cone is round and very large, with numerous wedge-shaped scales, and large eatable seeds or nuts, which have each a short, callous, marginal wing. The trunk is covered with a very thick corky bark; the wood is white, finely grained, and durable. The trees when wounded yield a milky juice, which hardens into a fine yellow resin; and the kernel of the nut, which is as large as an almond, is used by the Indians as an important article of food. The tree is a native of the Andes of Peru, and when first introduced it was called the Chilian Pine. It has now become quite common in this country, and the Earl of Harrington has planted an avenue with it at Elvaston Castle.
There are several species, but the other kinds are too tender to bear British winters without protection. The Norfolk Island Pine (A. excelsa) is a splendid tree, with light feathery foliage; as is the Moreton Bay Pine (A. Cunninghami).
§ II. CUPRESSINEÆ.—THE CYPRESS TRIBE.
Mostof the plants contained in this section are evergreen shrubs or low trees, but some of them attain a considerable size. Only one species, the deciduous Cypress, loses its leaves in winter. Many of the species are only half-hardy in Britain, and none of them are grown in this country for their timber. They all exude resin occasionally from their leaves and branches, but none of them produce turpentine. The catkins are but few flowered, and the cones are roundish. The leaves are frequently imbricated, at least when young; though in many of the species they vary considerably, even on the same tree.
THE GENUS THUJA.—THE ARBOR VITÆ.
Fig. 99.—Young plant of the Arbor Vitæ.
Fig. 99.—Young plant of the Arbor Vitæ.
Thereare several species of this genus, but only two are common in British gardens. Of these the American Arbor Vitæ (Thuja occidentalis) is the largest tree; though it seldomgrows above 30 feet high, and it is a great many years before it even attains that height.The male flowers and the female flowers are distinct, but on the same tree. The male catkins are small cones, with the pollen inclosed in four cases that are attached to the inside of the scale, near its base. The female catkins consist of six scales, with two ovules at the base of each; and the ripe cone has a sharp point projecting from each scale. The seeds have scarcely any wing; and when they germinate, they have only two cotyledons. The young plants send down a very long tap root (seefig.99), and have some of their leaves imbricated and others loose. The Chinese Arbor Vitæ (T. orientalis) seldom reaches the height of 20 feet, but it may be also distinguished from the preceding species by its more dense habit of growth, by its branches being turned upwards instead of spreading horizontally, and by its leaves being smaller, closer together, and of a lighter green.
THE GENUS CALLITRIS.
Callitrisis a genus separated from Thuja, of which only one species is as yet common in British shrubberies. This is the Gum Sandarach-tree, formerly calledThuja articulata, but now namedCallitris quadrivalvis. The branches of this tree are articulated, that is, they may be broken off at the joints without lacerating the bark. The leaves are very small, quite flat,and articulated like the branches. The male catkins form a cone, in which the scales are disposed in four rows, with three or four anthers at the base of each. The female catkins are solitary, and they divide, when ripe, into four woody valves or scales, only two of which bear seeds. The seeds are small, and have a wing on one side. The tree is a native of Morocco and Barbary, in which countries it produces the gum-sandarach, which exudes like tears from every part of the plant. The wood is fragrant, very finely grained, and extremely durable, as is shown in the roof of the Cathedral of Cordova, built in the ninth century, which is of the wood of this tree.
THE GENUS CUPRESSUS.—THE CYPRESS.
Theevergreen cypress (Cupressus sempervirens) is a cone-like, tapering tree, with its branches growing close to its trunk, and rarely attaining the height of fifty feet even in its native country. The male catkins are longer than those of the arbor vitæ, and the female ones contain more ovules. The cone is buckler-shaped, and it divides, when ripe, into eight or ten corky scales, each of which has four nuts attached; the cone being partially divided into cells, which may be seen, when the scales have been removed to show the interior. The pollen of each maleflower is contained in four cells, attached to the lower part of the inside of the scales. The wood is remarkably hard and fragrant, and it is of a fine close grain; it is also very durable. It is supposed to have been the gopher-wood of Holy Writ, and the citron-wood of the ancient Romans, the beauty of which in tables was so celebrated.
The White Cedar (Cupressus thyoides) is a species of Cypress, having imbricated leaves, and the same kind of cone; and the Cedar of Goa (C. lusitanica) is another species of Cupressus, which appears from the shape of its cones to be nearly allied to the Arbor vitæ. There are some other species, but they are not common in British gardens.
THE GEXUS TAXODIUM.—THE DECIDUOUS CYPRESS.
TheDeciduous Cypress (Taxodium distichum) has numerous leaves arranged in two even rows, one on each side of the branch, which fall off in autumn, assuming a reddish tinge before they drop. This genus was separated from Cupressus, because the male catkins, instead of being produced singly at the tips of the branches, are in clusters or panicles, and the anther-like scales, have the pollen in five cells. The cone, which is very small, has only two seeds to each scale, instead of four; and the young plant has fiveor more cotyledons, while the Cypress has only two. The deciduous Cypress was placed in the genus Cupressus by Linnæus, and afterwards it was calledSchubertia distichaby Mirbel. The tree, which grows 120 feet high and upwards in America, with a trunk forty feet in circumference at the base, has generally, when of this size, the lower part of its trunk hollow, often to the height of five feet or six feet from the ground. The roots also send up conical protuberances two feet high, and four feet or five feet wide, which are always hollow. These curious knobs are called in America “cypress knees;” and the negroes use them for bee-hives. The wood of the deciduous Cypress is used in building in Virginia. There is another species (T. sempervirens) which does not lose its leaves in winter, a native of California, but it has not yet been introduced.
THE GENUS JUNIPERUS.—THE JUNIPER.
The species of this genus are extremely variable in their leaves, which differ exceedingly on the same plant, and in the size to which the plants attain; as even the common Juniper, though generally a shrub not above three feet high, sometimes becomes a tree. In the common Juniper (Juniperus communis) the leaves are narrow and pointed, and they are placed inwhorls, three in each, round the branches. The male and female flowers are generally on different plants, but sometimes on the same. The male catkins are sometimes at the end of the shoots, but generally they spring from the axils of the leaves. The pollen cases vary from three to six, and they are attached to the back of each scale, which may be called the stamen (seeainfig.100). The female catkin, when young,Fig. 100.—Juniper(Juniperus communis).resembles a very small bud, and consists of three fleshy ovaries, almost hidden by the thick scales at their base. These ovaries grow together, and soon present the appearance shown, but magnified, atc. As they ripen, they rise out of the scales and become the fleshy strobile,b; and finally the spongy berry shown of its natural size atd, containing three seeds or nuts, each of which is flat on one side,f, and angular on the other,e, with five glandular indentations at its base. The berries are first green, but they afterwardsbecome of a dark purple, and are covered with a fine bloom. The Juniper berries are very fragrant, and the glands in their stones contain a kind of oil. These berries when crushed are used in making gin and hollands.
There are a great many species of Juniperus, but one of the most remarkable is the Red Cedar (J. virginiana). This is a tree forty feet or forty-five feet high. The leaves, when young, are scale-like; but when older they become loose and feathery, so that there are two kinds of leaves on the same tree. The male and female flowers are very small, and the berry is only two-seeded. The sap-wood of this tree is quite white, but the heart-wood is red, and it is used occasionally for making black-lead pencils, particularly those of the commoner kinds, though the Bermuda Juniper is preferred for the superior ones. This last species (J. bermudiana) is rather tender in England, and it is seldom grown in this country. Its berries are of a dark red, and they are produced at the ends of the branches; and the wood has so strong a fragrance that shavings of it are put in drawers to keep away moths. The Savin (J. Sabina), and several other species, have the old leaves scale-like, as well as those on the young wood. All the species have berry-like fruit, which is generally purple or dark red, and which varies principally in the numberof stones or nuts that it contains. The fruit of all the Junipers is very slow in ripening, and in some of the species it remains two years on the tree.
§ 3. TAXINEÆ.—THE YEW TRIBE.
The only needle-leaved tree in this section is the Yew, and this is the only one I shall describe; as though the Salisburia and some of the New Zealand resinous trees are included in it by modern botanists, the latter are at present very rare in this country; and the Salisburia, though it has been introduced more than a hundred years, and is frequently found in shrubberies, has not yet produced fruit in Britain.
THE GENUS TAXUS.—THE YEW.
Fig 101.—The Common Yew(Taxus baccata).
Fig 101.—The Common Yew(Taxus baccata).
The common Yew (Taxus baccata) has the male and female flowers on different plants.The catkins of the male flowers consist of a number of scales, out of which the anthers grow like a cluster of primroses, as shown, magnified, infig.101 ata. The female flowers somewhat resemble those of the Juniper; the ovary being enveloped in scales (b), from which it gradually emerges as it swells (c), till at last, when ripe (d), it opens at the top, and displays the ripe nut enveloped in a red juicy cup. The wood of the Yew is remarkably tough, and the growth of the plant is very slow.
To these may be added the very singular plants comprised in the order Cycadaceæ, which are on the debatable ground between the exogenous and endogenous plants. They bear cones like the pines and firs, but in their leaves, and the manner in which they unroll them, they resemble the ferns, and in the outside of their stems the palms; while from the wood being in concentric circles, they must be classed among the Exogens. It would be unsuitable to a work like this to enter into any of the discussions of botanists respecting these curious plants; it may be sufficient here to say that they are considered to be trees, the central cylindrical part being called the trunk; the soft pith in which, in some of the kinds of Cycas, is manufactured into a spurious sort of sago. The roughness on the stem arises from the remains of the footstalks of old leaves. Theleaves are pinnate, and unroll instead of unfolding. The flowers are male and female, both of which are produced in cones in Zamia; and the male flowers in cones in Cycas, while the female ones appear on the margin, and in the notches of abortive leaves, which spring in a mass from the centre.
MODERN BOTANY FOR LADIES.
MODERN BOTANY FOR SYNOPSIS OF THE NATURAL SYSTEM ACCORDING TO PROFESSOR DE CANDOLLE.
Allplants are by this system first divided into the Vasculares and the Cellulares; and to explain the difference between these two great divisions, it will be necessary to say a few words on the construction of plants, though this subject belongs properly to vegetable physiology. All plants are composed of two kinds of matter: viz. Cellular Tissue, which may be compared to the flesh of animals; and Vascular Tissue, which consists of spiral vessels and ducts, which may be compared to the nerves and veins. If any one will take the leaf of a hyacinth and break it by doubling it first on one side and then on the other, and will then draw the parts gently a little way asunder,the spiral vessels will be seen distinctly with the naked eye; as though very fine, they are sufficiently strong to sustain the weight of the lower part of the leaf for a short time. Now these vessels are much more conspicuous in some plants than in others; and in some of the inferior plants, such as lichens and fungi, they are wanting altogether. Their presence or absence has therefore been chosen to mark the two great divisions of the Natural System; the Vasculares being those plants which have both vascular and cellular tissue, and the Cellulares being those which have cellular tissue only.
The Vasculares are much more numerous than the Cellulares; and they are re-divided into sub-classes, which it also requires the aid of vegetable physiology to explain. All plants, when in a growing state, require the moisture taken up by their roots to be elaborated, and mixed with air in the leaves before it becomes sap; that is, before it is fit to contribute to their nourishment. Now, when a seed begins to germinate, its root descends into the ground and its plumule, or ascending shoot, rises upwards; but the leaves folded up in the latter are too weak and tender to elaborate the sap; and besides, they cannot act till they are fully expanded, and they want nourishment to give them strength to unfold; the roots are also notsufficiently developed to absorb moisture. To supply the wants of the young plant while it remains in this feeble and imperfect state, a quantity of albumen is laid up in the seed; and it is evident that this substance must be extremely nourishing, as it forms, when ground, what we call flour. The young plant is thus provided with food, till its roots are sufficiently developed to obtain it from the soil; and to enable it to elaborate this food and to turn it into sap, it is, in most cases furnished with one or more seed-leaves,Fig. 102.—Cotyledons, Leaves, and Wood of a Dicotyledonous Plant.or cotyledons, (seecinfig.102,) which drop off as soon as the true leaves are sufficiently advanced to be able to perform their proper functions. The cotyledons differ in number, form, and substance in the different genera; but in all plants, they are very different from the true leaves, being admirably contrived for answering the end for which they are designed; and it having been found that the plants having two or more cotyledons differ widely in many other respects from those having only one cotyledon, the number of the cotyledons has been chosen as the distinguishing mark of the second great division of plants according to the Natural System.
The Vascular plants are therefore again divided into the Dicotyledonous plants, which have two or more cotyledons; and the Monocotyledonous plants, which have only one cotyledon: and to these modern botanists add the Acotyledonous plants, which have no cotyledon, as some of them have spiral vessels, or at least ducts, though most of the Acotyledonous plants belong to the Cellulares. These divisions are not only marked by their cotyledons, but they are so distinct in other respects, that it is sufficient for a botanist to see a leaf, or even a bit of wood without leaves, of any plant, to know at first sight to which of these three divisions the plant belongs.
If the leaf of a Dicotyledonous plant be examined, it will be found to have a strong vein up the centre, from which other veins proceed on each side (as shown atainfig.102); and if it be held up to the light, the rest of the leaf will be found to be intersected by numerous smaller veins, so as to appear like network, and hence these leaves are said to be reticulated. The trunk and branches of trees belonging to this division consist, when young,of pith, wood, and bark. At first the substance within the bark is little more than pith, but as the returning sap deposits every year a layer of wood just within the bark, which presses against the previous layers so as to contract them, they press in turn against the pith, which becomes smaller and smaller every year, till at last, in old trees, it is scarcely perceptible. The layers of wood are always perfectly distinct from each other, and they are called concentric rings (b); while faint lines, with which they are intersected, and which proceed like rays from the remains of the pith in the centre, are called medullary rays. A layer of wood being deposited every year, the age of the tree may be discovered by counting the concentric rings; also if the tree has grown rapidly, the layers will be thicker than if it has grown slowly; and if it has had one side more exposed to the sun than the other, the remains of the pith will be on one side instead of in the centre, and the layers will be thinner on that side than on the other. The newest layer of wood, which is called the alburnum or sap-wood, is of a paler colour and more porous texture than the rest of the tree, and it is of less value as timber. It is from the manner in which the successive layers of wood are deposited that Dicotyledonous trees are called exogens, which signifies, to increase from the outside.
If the leaf of a Monocotyledonous plant be held up to the light, the principal veins will be found to form parallel lines of nearly equal thickness, the central one being very little, if any,Fig. 103.—Monocotyledonous Plant.larger than the others (seeainfig.103). The trees belonging to this division are all natives of the tropics, and their softest and newest wood is in the centre, where fresh deposits are made every year inside the old wood; and hence, these trees are called endogens, which signifies, to increase from within. The wood of these trees has neither medullary rays nor concentric rings; and a section of it appears pierced with numerous holes (b), as may be seen by cutting off a slice of bamboo. The germination of a Monocotyledonous plant, with the cotyledon remaining in the ground, is shown atc.
The Dicotyledones and the Monocotyledones have all visible flowers, and are hence called Phanerogamæ; but the Acotyledones have no visible flowers, and they are hence called Cryptogamæ, which signifies that their flowers are hidden. The most remarkable of the Cryptogamous plants are the ferns, some of which become lofty trees; the wood of which is in curious wavy lines, as it appears to be formed by the footstalks of the decayed leaves growing together and becoming woody. The veins in the leaves or fronds of the ferns are forked.
Besides the great divisions already mentioned, the Dicotyledonous plants have been divided into the Dichlamydeæ, or those having both calyx and a corolla; and the Monochlamydeæ, or those having only a calyx; but there are so many exceptions, as to render this division of little value. The Monochlamydeæ are not subdivided, but the Dichlamydeæ are again divided into the Thalamifloræ, in which the petals and the stamens grow separately out of the thalamus or flat part of the receptacle, and generally from below the pistil; the Calycifloræ, in which the stamens and petals are either attached to the calyx, or to a lining of it formed by the dilated receptacle; and the Corollifloræ, in which the petals grow together, so as to form a cup for the pistil, and which have the stamens attached to the corolla, but quite distinct from the calyx. The Monocotyledones have also been re-divided into the Petaloid, or those with regular flowers,like the bulbous plants, and Orchidaceæ; and the Glumaceous plants, or those with scales or glumes instead of petals, as in the sedges and the grasses. The Acotyledones are divided into those with leaves, as the ferns; and those without leaves, as the mosses, lichens, and fungi.
I have only to add that each sub-class is divided into numerous orders, which are differently arranged by different botanists; the object being to place those nearest together which are most alike. As no one of these arrangements appears to be decidedly better than the others, I have adopted that given in Mr. Loudon’sHortus Britannicus; marking, where, they occur, the new orders which have been formed, and the alterations in the old ones that have been made since that work was written.
PHANEROGAMOUS PLANTS—DICOTYLEDONÆ—I. DICHLAMYDEÆ.
§ I.—THALAMIFLORÆ.
Inall the plants contained in this chapter the receptacle is a fleshy substance called the thalamus, or disk, which is surrounded by the calyx, and out of which the carpels or seed-vessels, the stamens, and the petals, all grow separately from each other. Sixty-five orders are included in this division, but I shall only describe those which contain plants which have been introduced into Britain, except where the orders chance to contain plants well known in commerce.
ORDER I.—RANUNCULACEÆ.
Theplants belonging to this order are known by their numerous stamens, the anthers of which burst outwardly; by their carpels growing close together without adhering, except in one or two instances; and by the stem-clasping petioles of their leaves, which are generally deeply cut. The flowers when regular have five petals and five sepals, but they differ widely in shape, and the calyx of several of them is coloured so as to resemble a corolla. The seeds are frequently cariopsides; and the plants abound in a watery juice which is acrid, and in most cases poisonous.
ORDER II.—DILLENIACEÆ.
Thisorder resembles Raminculaceæ in having five petals, five sepals, and numerous stamens; but the anthers burst inwardly instead of outwardly, and there are never more than five carpels, and seldom more than two, which often grow into a berry-like fruit, as in the genus Dillenia from which the order takes its name. One species of this genus is occasionally seen in English hothouses,Dillenia speciosa. It has yellow flowers with the five petals apart at the base, and the sepals edged with white. The fruit consists of five carpels growing together with a sort of crown formed by the spreading stigmas. Another genus, some of the species of which are found in British greenhouses, isHibbertia. The species are generally climbing plants, with flowers like those of Dillenia, but smaller, thoughH. dentatahas the petals close together. The difference between the genera consists principally in the carpels, which in Hibbertia are distinct with long filiform styles curving inwards. All the plants contained in this order are evergreen exotic shrubs and trees with simple alternate leaves, and, with only two or three exceptions, the flowers are yellow.
ORDER III.—MAGNOLIACEÆ.
Thisorder was divided by De Candolle into two tribes: viz.Illicieæ, the Aniseed tribe; andMagnolieæ, the Magnolia tribe. The first, which is now made a distinct order, under the name of Winteraceæ, contains three genera, only one of which, Illicium, is common in this country. The only hardy species of this genus,I. floridanum, the Florida Aniseed tree, has very dark purple flowers, which appear to be double from the great number of the petals, which are from twenty to thirty. The carpels are also numerous, and arranged so as to form a star. All the plants in this tribe are highly aromatic, and one species,Drimys Winteri, which has white fragrant flowers, produces an aromatic bark that is used in medicine.
The tribe Magnolieæ is distinguished by the fruit consisting of a number of carpels arranged so as to form a cone. There are six genera in this order, the most remarkable of which are Magnolia, Liriodendron, Talauma, and Michelia, the last genus consisting of stove trees, with very fragrant flowers, which are generally of a pale yellow, and only one species of which,M. Champaca, has been introduced.
Of these genera Magnolia is undoubtedly the best known; as nearly all the species arecommon in British gardens. This genus is divided into two sections, one containing the American Magnolias, and the other those from Asia, which are principally from China and Japan.