foem. ovariis ovato-globosis stigmatis lobis maximis. Ph. Am. 2. p. 619. Rich. App. p. 38.
Pall. Ross. 1 .t. 41. Trew, Ehret. t. 46.—a. pedunculo foem. pubescente, florum pedicellis
vix perianthii glabri longitudine, foliis?—/3. pedunculo foem. glabro, pedicellis pistillo
longioribus, foliis cordatis acuminatis basi truncatis.—y. amends ubique (etiam ovariis)
pubescenti-tomentosis, floribus sessilibus, foliis exacte cordatis acuminatis. an species
distincta?
H ab . Canada. Mrs Sheppard. Throughout the woody country to the Great Slave Lake, and the south
branch of the Mackenzie River, called Riviere aux Liards, from the great quantity of this tree which grows
there. It constituted the greater part of the drift timber observed on the shores of the Arctic Sea. Dr
Richardson.—,fi. Newfoundland. Miss Brenton.—X Banks of streams, N.W. America, attaining to a very
large size, 60-140 feet high, and 9-20 feet in diameter. Douglas.—The trees in general, I fear, and the
Poplars in particular, have not received that degree of attention that they deserve from the writers on
American Botany. The leaves are very liable to vary, and it is remarkably the case with this species, as
may be seen by the.figures of Trew and Pallas; but they are never white on the underside, as described by
Willdenow, &c. The flowers, too, are liable to vary, if I am correct in referring my two varieties to the
present species. The y., from the Pacific side of America, will probably prove a distinct species; but I
possess only one specimen, and that with nearly perfect fruit: the amentum is a span long, and the capsu es
as large as pease, all over downy, and they are quite sessile. The leaves and flowers, both of fi. and y., are
very similar in form to those of P. monilifera, but the toothing and under surface are considerably different.
My specimens of P. balsamifera, from Kamtschatka, have the foliage orbicular, with scarcely any acumen.—
Dr Richardson observes that the trunk of this attains a greater circumference than that of any other tree in
the northern parts of America.
2. P . candicans (A it.); foliis cordatis acuminatis subtus albidis subtriplinerviis, stipulis
resinosis ramis teretibus. Ait. Hort. Kew. ed. 1. v. 3. p. 406. Ph. Am. 2. p. 618.
H a b . Canada. D r Hope.' (Ait.)—Of this species I am ignorant, and Willdenow, Pursh, and Michaux,
have added nothing to the brief character given by Aiton. Indeed Micbaux’s figure and description, in the
N. American Sylva, are alike unsatisfactory on the subject of the Poplars. From Dr Schweimtz I have
received the following species, under the name of P. candicans. May they not in reality be one and the
same?
3. P . grandidentata (Mich.) ; ramis teretibus, petiolis supeme compressis, folus rotun-
dato-ovatis vix acuminatis grosse irregulariter sen angulato-dentatis basi saepe biglandu-
losis glabris jjmioribus densissime cano-tomentosis, amends fcemineis longis laxis, ovariis
lanceolatis, stigmatis lobis linearibus. Mx. Am. 2. p. 243. N. Am. Sylv. p. 243. t. 99, f. 2.
(good as to the fully formed leaf).
H ab . Canada. Ph. M r, Sheppard. Lake Huron. Dr Todd. New Brunswick. * Kendal.-The
foliage puts on very different appearances at different periods of its growth, the young leaves being clothed
with very dense white tomentum, and margined with rather small and nearly regular teeth ; as they advance
in age. the down disappears, and the teeth become very large, and irregular.
4. P . treniuloides (Mx.) ; ramis teretibus, foliis parvulis suborbiculatis breviter acumi-
nulatis serrulatis ciliatis basi ssepe biglandulosis, squamis masculinis pulcherime sericeis,
ovariis lanceolatis, stigmatis lobis linearibus. Mx. Am . 2. p . 243.(1803). N. Am. Sylv.
p. ‘242. t. 99. ƒ. 1.—P. trepida. mild. (1805).—Ph. Am. 2. p. 618. Rich. App. p. 38.
H ab. Canada (Mx. Mr, Sheppard), ta far as lat. 64°. D r Bichardtm. Dougla,. New Brunswick.
Mr Kendal. Newfoundland. Miss Brenton.—The wood is remarked by the Crees to burn better in a green
state than that of any other tree. In other respects it is worthless.
(The P. laevigata, Willd., received the name of Canadensis, from an idea that it was introduced into
France from Canada; but that is mere conjecture, and as I have never received specimens except from the
Unitpd States, I do not venture to introduce it. The P. monilifera, Wats. Dendrol. t. 102, is a good representation
of this plant, and I strongly suspect that Michaux’s plant of that name is no other. The female
flowers very much resemble those of P. balsamifera, but the leaves are very different.)
Subord. II. Betuline2E. Rich.
3. BETULA. L.
1. B. populifolia (Ait.); “ foliis deltoidibus longe acuminatis inaequaliter serratis
glaberrimis, amends foem. cylindraceis, squamis lobis lateralibus oblongis, decurvo-falcatis,
intermedio breviori, petiolis glabris.” Hort. Kew. ed. 1. v. 3. p. 336. Mich. N. Am. Sylv.
p. 91. t. 71. Ph. Am. 2. p. 620.
H a b . Canada. Ph.—My own specimens of this are all from the United States; and I confess that, except in
the narrower and rather more compact female catkins, and the smaller scales (for the shape is the same in the
two), I cannot see how it differs from the European B . alba. The leaves are the same in both.
2. B. papyracea (Ait. Hort. Kew. ed. 1. p . 337.); foliis subcordato-ovatis brevi-acumi-
natis subasqualiter serratis subtus punctatis glabris nunc ad axillas venarum hirsutis,
amentis foemineis lato-cylindraceis, squamarum lobis lateralibus oblongis decurvo-falcatis
intermedio subbreviori. Ph. Am. 2. p. 621.
H a b . Canada. (Ph.) Lake Huron (Dr Todd) to lat. 65°. Dr Richardson. Drummond. Douglas
(who observes it is rare to the west of the Rocky Mountains).—Mr Drummond’s specimens have only the male
catkins perfect, and no leaves. In my specimens from Dr Torrey (Massachusetts) the female catkins are
pendent, and the leaves are slightly downy beneath on the nerves, and have there, in the axils of the nerves,
generally a dense woolly tuft. My specimen from Atabasca, gathered by Douglas, has the female catkins
erect, the leaves quite glabrous, and the young branches rough with resinous warts. In all, the leaves are
dotted beneath, in consequence of copious resinous exudations.
3. B. occidentalis; ramis rufo-fuscis copiose resinoso-verrucosis, foliis late rhombeo-
ovatis sublobatis grosse inciso-serratis sub lente appresso-hirsutulis v. nudis subtus palli-
dioribus epunctatis, nervis paucis remotis, amentis foem. lato-cylindraceis, squamis lobis
ovato-oblongis lateralibus decurvo-falcatis intermedio longiore.
H ab. Straits of De Fuca. Dr Scouler. Near springs on the west side of the Rocky Mountains. Douglas;
and on the east side, from the mountains to Edmonton House. Drummond. One specimen is in the collection
from the Arctic coast.* (?) Dr Richardson.—This Birch does not agree with any described species,
and it is probably confined to the west coast, and to the immediate vicinity of the Rocky Mountains, forming
a low, small brush-wood, 6-10 feet high, and never exceeding a few inches in the diameter of its trunk.
Mr Drummond considered it to be the B. nigra, but its bark and leaves are quite different; the latter
remarkable for the few and remote nerves, which spring from thé mid-ribs : besides, B . nigra is a southern
tree of great size. The main branches are erect, and somewhat virgate, clothed with a red-brown bark a
little inclining to purple, copiously sprinkled with resinous warts in all the specimens. Petioles £ to f of
* There has probably been some mistake in the station of this.