300 SALICACE.S. 



tomentum: aments on lateral leafy branches, and some terminal, often sev- 

 eral together on a vigorous shoot, linear-cylindrio; scales yellowish- 

 villous, toothed, deciduous: stamens 2: capsules oblong-oonio, obtuse, 

 usually tomentose. — Common, but chiefly at some distance from the Bay. 



5. S. lasiolepis, Benth. Tree sometimes 30 or 40 ft. high, with 

 smooth grayish trunk and broad rounded head: leaves oblanceolate or 

 oblong-lanceolate, 3—5 in. long, obliquely acute or acuminate, more or 

 less strongly pubescent when young; or even in age, coriaceous, une- 

 qually serrate, glaucous and somewhat ferruginous beneath; stipules 

 mostly none: aments subsessile, appearing long before the leaves, cylin- 

 dric, dense; scales rounded, blackish, densely white-silky, persistent: 

 stamens thrice as long as the scale: filaments slightly united at base: 

 capsules dark green, glabrous, acute. — The most abundant of willows, in 

 the Bay region; found along all streams, and in all springy places. 



6. S. Bigelovii, Torr. Only a low tufted shrub, seldom 8 or 10 ft. 

 high; branches very stout, pubescent: leaves obovate, or cuneate-oblong, 

 obtuse, entire, silky-pubescent beneath: aments on short villous some- 

 what leafy peduncles, short and dense: ovary ovate, pedicellate. — 

 Apparently confined to moist depressions among the sand hills near San 

 Francisco; early-flowering like the last; in our opinion distinct from it. 



7. S. Sitchensis, Sanson. Shrub 6—15 ft. high, with straggling 

 rather slender recurving branches: these pubescent when young, sometimes 

 glaucous: leaves oblong-obovate to oblanceolate, acute, or the earliest 

 obtuse and cuspidate-pointed, the base narrowed to a short petiole, lus- 

 trous-white and satiny -tomentose beneath, margin entire or obsoletely 

 crenulate: aments erect, slender, dense: scales yellowish or tawny, 

 sparsely villous: stamen solitary: capsule ovate-conic, acute, tomentose. 

 — Banks of streams among the higher hills. 



2. POPULUS, Pliny (Poplar). Trees with branchlets somewhat 

 angular. Buds with several and imbricated scales. Bracts of the aments 

 lacerately toothed or fringed. Stamens few or many, inserted on an 

 obliquely truncate disk; filaments filiform; anthers purple. Capsule 

 ovate-oblong to globose, 2— 4-valved. 



1. P. trichocarpa, Torr. & Gray. Tree of somewhat conical outline, 

 30 — 50 ft. high: buds shining and viscid: leaves broadly ovate to oblong- 

 lanceolate, acuminate, 2 — 4 in. long, crenate, finely puberulent when 

 young, in maturity pale beneath; petioles terete, 1 — 2 in. long: staminate 

 aments dense, 2 in. long; bracts slightly villous: rachis pubescent: disk 

 broad, slightly pubescent; filaments as long as the anthers: pistillate 

 aments 2 in. long (becoming 6 in.); rachis pubescent; bracts and dilated 

 disk nearly glabrous; ovary densely pubescent; styles 3, broadly dilated 

 and lobed: capsules almost sessile, subglobose, pubescent, 3-valved, Jj in. 

 thick: seed light-colored. — Along the larger mountain streams. 



