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. fl. Alt. vol iv .p. 297, Sfc. 

 t. 479. P. balsamifera, Pallfior. Boss. t. 41. fig. 13. Spach. 

 I. c. p. 33. 



Tree tall, pvramidal, 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 ot 



the leaves. 



Leaves fat, 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. 1 hird rib 

 but little dilated towards the insertion of the petiole. Leaves 

 of young trees stronger and often undufeted. 



N.B. A specimen brought by Mardovkin from the Altai 

 regions had perfectly and broadly ovate leaves (almost like 

 Hibiscus svriacus), five-nerved, coarsely crenated. It *as 

 first introduced by Ledebour from that country. It stands 

 the hardest frost. 



35. Populus suaveolens, Fkch. P. balsamifera, Pallfior. 

 Boss. 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 



