1640

ARBORETUM AND I’RUTICETUM.

PART III.

perty that it will not, like any resinous wood, readily take fire.” (Smith inEng. FI.)

Varieties referable to one or other of the preceding kinds, most of them toP. alba.

31 P. a. 2 hybrida Bieb. Fl.Taur. Cauc., 2. p. 423., and Suppl., p. 633.; P.alba Bieb., 1. c.; ? P. intermedia Mertens ; P. a. crassifolia Merten-,and P. grisea Lodd. Cat. , 1836; appears to be intermediate betweenP. alba and P. (a.) canescens. It is plentiful in the neighbourhoodof streams in Tauria and Caucasus; whence it appears to have been

, introduced into Britain in 1816. There is a female plant of thiskind in the Horticultural Society’s Garden, and young plants inLoddiges’s arboretum.

JP.a.3 a cerifdlia; P. acerifolia Lodd.Cat., ed. 1836 ; P. juercifolia Hort. ;P. palmata Hort.; is a very distinct variety of P. alba, with theleaves broad, and deeply lobed, like those of some kinds of d'cer.

X. P. a. 4 arembergica, P. arembergica Lodd. Cat. , 1836, seems identicalwith P. (a.) acerifolia; but the plants in Loddiges’s collection, whichwere only received in 1835, are so small, that it is difficult todecide with certainty respecting them. Booth ( Gard. Mag., xi.p. 207.) describes it as growing much more rapidly than the old variety.

If P. a. 5'belgica, P. belgica Lodd. Cat. , ed. 1836, is also a kind removedfrom the Continent in 1835 ; but the plants in Messrs. Loddiges’scollection are too small to admit of our stating anything more re-specting them, than that they are evidently a variety of P. alba;probably identical with P. a. acerifolia.

X P. a. 6 candicans, P. candicans Lodd. Cat. ,ei. 1836, is a strong-growingvariety of P. alba; probably also identical with P. acerifolia. Thisis the P. tomentosa of the Hawick Nursery , and the hoary poplar ofthe Edinburgh nurseries, where it is propagated by layers, whichmake shoots 6 ft. or 8 ft. long the first season.

If P, a. 7 nivea, P. nivea Lodd. Cat. , differs very little, if at all, from thepreceding variety.

X P. a. 8 eegyptiaca Hort., P. a. pallida Hort., the Egyptian white poplar,is a much weaker-growing plant than any of the preceding varieties;though we have received specimens of this kind from the HawickNursery , and seen a tree bearing this name in the HorticulturalSociety’s Garden, we can say very little about it. Messrs. ArchibaldDickson and Son, of Hawick , state that it is unfit for planting forforest purposes.

Other Varieties. The late Professor Mertens of Bremen (as M. Fis-cher of Gottingen informed us in 1835) planted a number of differentsorts of poplar on the ramparts of Bremen; and, in 1816, specimensof these were sent to Sir J. E. Smith , which are now in the herbariumof the Linnaean Society . Of these specimens, the most remarkable is

P. a. 9 pendula , P. a. var. gracilis rkmis pendentibus Mertens. — The specimens of this va-riety are of both sexes; and we may presume, from the pendent shoots, that it wouldbe a very desirable kind of poplar to have introduced, if it is not already in this country.There is a pendent-branched tree of P. alba in Lincoln’s Inn New Square, which mightprobably retain its drooping character, if propagated by cuttings or grafting.

Description, §c. The white poplar, and its different varieties, form treesfrom 80 ft. to 100 ft. high, and upwards, generally with a clear trunk to a con-siderable height, and a spreading head, usually, in full-grown trees, but thinlyclothed with foliage. The roots creep under the surface to a considerabledistance from the tree, and send up suckers in abundance. The leaves of althe varieties are white underneath; those of P. (a.) canescens least so; anathose of P. a. nivea, and P. a, candicans, so in the greatest degree. H*eleaves of the largest-growing varieties of the abele tree, are deeply lobed anaindented; very dark above, and very white and downy beneath, with f° ot jstalks about lin. in length. The young shoots have a purplish tinge, an

they are covered with a white down; but the bark of the trunk and oi t e