SYSTEMATIC BOTANY. 



is used by the Esquimaux and others in the con- 

 struction of canoes. The common alder (A. 

 glutinosa) is a quick-growing tree, found in 

 swampy flats and by the borders of streams ; its 

 wood resists well the action of water, and is useful 

 for piles ; the Rialto at Venice is built on alder- 

 piles, as well as many houses in Amsterdam ; the 

 hoary alder (A. incana) is seldom found south 

 of the sixtieth parallel ; the notch-leafed alders 

 (A. sinuolata and A. glauca) are both American 

 species. 



The bark of the order is astringent and bitter. 

 A decoction of birch-bark is used by the Lap- 

 landers in the preparation of reindeer skins ; and 

 the empyreumatic oil derived from it is used by 

 the Russians in tanning, which gives the peculiar 

 odour of their leather. The sweetish sap obtained 

 by tapping the birch in spring is the chief ingredient 

 in birch-wine ; the leaves, which, when young, 

 are highly odorous, are also used in imparting 

 dyes of various shades of yellow. B. lenta yields 

 sugar. 



CORYLACE.*. The Corylaceae or Cupuliferae are 

 so named from the cup-like shape of the persistent 

 involucre in which their fruit or nuts are placed 

 as, for example, the acorn. The order includes 

 many genera of well-known trees and shrubs as 

 the oak, Spanish chestnut, beech, hazel, and horn- 

 beam. Their leaves are alternate, simple, and 

 stipulate ; their venation well marked, and often 

 rigid ; flowers, unisexual ; the males in catkins, 

 and the females in clusters or in catkins ; the male 

 flowers have from five to twenty stamens inserted 

 into the base of the scales, or of a membranous 

 perianth, generally distinct ; in the females, the 

 ovaries are crowned by the rudiments of an 

 adherent perianth, seated within a coriaceous 

 involucre of various figure, and with several cells 

 and several ovules, most of which are abortive ; 

 ovules, twin or solitary, pendulous ; stigmas, seve- 

 ral, nearly sessile, and distinct ; fruit, a bony or 

 leathery nut, of one cell, and more or less inclosed 

 in the involucre. 



The following are the most familiar genera : 

 Quercus, of which Q. pedunculata and sessiliflora 

 are the British oaks ; Q, suber, the cork-tree ; Q. 

 I/ex; the evergreen oak ; Q. rubra, the scarlet oak 

 of America ; Q. infectoria, the gall-yielding oak ; 

 and Q. cocci/era, the kermes oak. Fagus, of which 

 F. sylvatica is the common beech of our woods ; 

 and F. ferruginea, of North America, has edible 

 fruit. Castanea, to which belong C. vesca, the 

 edible sweet chestnut ; and C. pumila, the dwarf 

 Virginian chestnut. Corylus, of which C. Avel- 

 lana is the common hazel-nut or filbert, which 

 yields an oil used by artists and watch-makers. 

 Carpinus Betulus, the hornbeam of our hedges ; 

 and Ostrya Virginica, the iron-wood of America. 

 The hornbeams are by some botanists ranked 

 under the Birch tribe, on account of the involucre 

 not forming so complete a cupule as the other 

 genera ; but this seems too minute a distinction, 

 as the involucre is not more leafy than it is in 

 some of the filberts. The members of the family 

 abound in Europe, Asia, and North America, and 

 generally in temperate regions, more sparingly in 

 South America ; they are altogether absent from 

 the south of Africa. 



The bark in all the species is bitter and astrin- 

 gent, and is used for dyeing, tanning, and for 

 medical purposes. In a few, the fruit is bitter 



and disagreeable ; but in the majority it is farina- 

 ceous, and frequently contains an oily matter, used 

 in domestic economy. Their fruit, as well as their 

 bark and timber, is of the highest value to man. 

 The gall-nut is an excrescence of the oak caused by 

 the puncture of an insect ; it is used in medicine, 

 and in the manufacture of ink and black dyes. 



GYMNOSPERM^E. 



CONIFERS. One of the most important, as it 

 is one of the best defined, of the natural orders. 

 Its members are trees or shrubs, with a sym- 

 metrically branched trunk abounding in resin, 

 and are familiarly illustrated by the Scotch pine, 

 the spruce and silver firs, the larch, the cedar, 

 the araucaria, the arbor vitae, the cypress, and the 

 juniper. The ligneous tissue of their wood is 

 marked with circular discs having a central 

 punctation ; their leaves are linear, needle-shaped, 

 or lanceolate, entire at the margin. The charac- 

 ters afforded by the fructification are : Flowers, 

 unisexual ; males in deciduous catkins, monan- 

 drous or monadelphous, each floret consisting of 

 a single stamen, or of a few ; females in cones, 

 whose scales arise from the axil of membranous 

 bracts supplying the place of ovaries ; destitute 

 of a proper style or stigma ; ovules, naked, in 

 pairs on each scale, with large micropyles at 

 their apices ; fruit consisting of a cone formed 

 of the hardened scales, which become enlarged 

 and indurated, and occasionally of the bracts 

 also ; seed, with a hard crustaceous testa. In 

 speaking of the Coniferas, it has been not inaptly 

 remarked that ' the flowers are quite different from 

 what is generally understood by that name, being 

 in fact nothing but scales ; those of the male con- 

 taining the pollen in the body of the scale, and 

 those of the female producing the ovules or in- 

 cipient seeds at the base.' 



Well defined as the order obviously is, there 

 are minor distinctions which warrant its sub- 

 division into the following sections namely, 

 ABIETINE^E, the true pines and firs ; and Cu- 

 PRESSINE^E, the cypresses. In the firs, the fruit 

 is a cone, the scales of which open, and more 

 or less recurve, when the seeds are ripe ; the 

 ovules are inverted ; the pollen, oval, or curved : 

 in the cypresses, the fruit is also a cone, but 

 rounder, and with fewer scales, occasionally 

 succulent, forming a galbulus ; ovules, erect; pol- 

 len, spheroidal. Of the Abietineae the following 

 are characteristic members : Pinus sylvestris, the 

 Scotch pine ; Abies 'excelsa, the spruce-fir; Picea 

 pectinata, the silver fir ; Larix Europeea, the com- 

 mon larch ; Cedrus Libani, the cedar ; and Arau- 

 caria imbricata, the Chili pine all of which arc 

 evergreens, with the exception of the larch. The 

 Cupressineae are well represented by Cupressus 

 scmperviretis, the evergreen cypress ; Thuja occi- 

 dentalis, the American arbor vitas ; Taxodium 

 distichum, the deciduous cypress ; Juniperus com- 

 munis, the juniper of our moors ; J. sabina, the 

 savin-tree, as well as by the newer geaera, Saxe- 

 Gothaa, Fitzroya, &c. 



The high importance of this order is derived 

 from its timber, which in all is straight, easily 

 worked, and durable. Wellingtonia gigantea, the 

 mammoth tree of California, forms a lofty trunk 

 112 feet in circumference, and upwards of 350 

 feet in height. Many valuable additions have 



