23 
Leaves spreading, flat, in adult trees ovate, or roundish 
ovate, shortly acuminate, sometimes slightly cordate, not 
rarely somewhat cuneate at the base, five-nerved, often with 
an additional pair of slender nerves, closely and slightly cre- 
nated ; crenatures covering very minute glands ; above bright 
green, beneath whiter, minutely reticulated. 
Leaves on young trees in a less degree, but by no means 
shortly petiolated, ovate, oblong. 
N.B. Found planted about St. Petersburgh and Moscow, 
and supposed to be of foreign introduction. Probably Ame- 
rican. 
34. Populus laurifolia, Ledeb. jl. Alt. vol. iv .p. 297, Spc. 
t. 479. P. balsamifera, Pall.fior. Ross, t. 41. fig. 13. Spach. 
1. c. p. 33. 
Tree tall, pyramidal, bright green ; branches very angular, 
grey, in adult trees stoutish. Buds swollen, yielding a balsam 
smelling of storax. 
Stipules erect, mucronate, balsamiferous. 
Petioles at the lower end roundish, compressed towards 
the apex, with a very narrow furrow, short, those of the 
cordate leaves generally shorter, and of the oblong-lanceolate 
leaves larger ; from half to six times shorter than the blade of 
the leaves. 
Leaves flat, sometimes oblong, even, lanceolate-oblong, and 
attenuate at the base, sometimes ovate-oblong, rounded or 
cordate at the base, acuminate, acute, triple-nerved, often with 
an additional pair of nervures at the sides, closely and minutely 
crenated ; crenatures remarkably glandular ; bright green, be- 
neath paler, not opaque, reticulated, tolerably firm. Third rib 
but little dilated towards the insertion of the petiole. Leaves 
of young trees stronger and often undulated. 
N.B. A specimen brought by Mardovkin from the Altai 
regions had perfectly and broadly ovate leaves (almost like 
Hibiscus syriacus), five-nerved, coarsely crenated. It was 
first introduced by Ledebour from that country. It stands 
the hardest frost. 
35. Populus suaveolens, Fisch. P. balsamifera, Pall.fior. 
Ross. t. 61. principal figures and letters , Sfc. 
Tree with us middle sized pyramidal, in Dahuria, according 
to Pallas, a shrub, with a greyish green aspect; branches 
