S A L I C A C E M. 469 



Territory, and down the river to the sea. On the Pacific coast it 

 does not appear to extend much south of the Columbia, except along 

 the Willamette, but to the east it is common on the upper tributaries 

 of the Missouri, thence south to the mountains of New Mexico. In 

 Oregon it attains its greatest magnitude, being nearly as large as P. 

 monilifera. It is very near P. longifolia, Fisch., which Loudon re- 

 gards as a narrow-leaved variety of the following species. 



4. POPULUS BALSAMIFERA, Limi. 



Populus bakamifera, Linn. Sp. p. 1464 ; Michx. Sylv. 2, t. 93 ; Hook. FI. Bor.- 

 Amer. 2, p. 153 ; Loud. Arb. p. 830, fig. 1507-1510. 



Hab. Banks of the Columbia.— This is called Balsam Tree and 

 Balsam Poplar in Oregon, where it is frequent, and ranks among the 

 tallest of the deciduous trees. The leaves in all the specimens are 

 ovate or oblong-ovate, scarcely at all acuminate, and mostly rather 

 acute at the base, finely serrate-toothed, the under surface very pale 

 or whitish, and smooth. 



5. Populus trtchocarpa, Torr. & Gray, 



Populus trichocarpa, Torr. & Gray in Hook. Ic. 9, t. 878; & in Bot. Whippl. Eep. 



p. 204. 

 P. bakamifera, var. Hook. Fl. Bor.-Ainer. 2, p. 154. 



Hab. Along rivers, between Puget Sound and the Cascade Moun- 

 tains, Washington Territory. — This seems to be a common species in 

 the Pacific States. Dr. Pickering in his notes remarks that it is a tall 

 tree, but he does not state the height. It is allied to P. balsamifera, 

 but is readily distinguished by the subglobose, hairy, and closely 

 sessile fruit. The foliage greatly resembles that of P. candicans, 

 which Hooker considers a variety of P. balsamifera. It is undoubt- 

 edly his last variety of the latter species, but he does not quote the 

 synonym in his Icones. 



lis 



