Populus.] cxxvi. sALiciNE^ (Skan). 325 



2. POPULUS, Linn. ; Benth. et Hook. f. Oen. PI. iii. 412. 



Flowers dioecious. Disc more or less cupshaped, often oblique, 

 entire, toothed or irregularly lobed, fleshy or membranous. Mule 

 flowers : Stamens 4-30 ; filaments filiform, free ; anthers often 

 rather large. Female flowers : Ovary sessile inside the disc ; 

 placentas 2-3, more rarely 4 ; style short, with as many branches 

 as the })lacentas, entire or 2-fid ; ovules many or often very many 

 on each placenta, 2-oo-seriate. Capsule 2-3-valved, more rarely 4- 

 valved. Seeds of the order. — Trees with teret e or angular branchlets ; 

 buds scaly, often resinous. Leaves alternate, usually broad, pin- 

 nately veined and 3-nerved at the base, entire, toothed or lobed ; 

 stipules narrow, membranous, deciduous. Flowers in loose catkins, 

 usually shortly pedicellate in both sexes. Catkins usually more or 

 less pendulous, appearing before or rarely with the leaves. Bracts 

 often contracted into a stalk, dilated, toothed or ciliate-fimbriate 

 at the apex, not rarely very fugacious. 



Species 30 to 40, or according to some authorities over 120, in Europe, 

 Northern and Tera])erate Asia, North and East Tropieal Africa, and North 

 America southwards to Northern Mexico and Lower California. 



1. P. Denhardtiorum, Dode in Bull. Soc. Dendr. France, 1909, 152. 

 A deciduous tree, 60-80 ft. high; branchlets at first shortly grey- 

 pubescent, soon glabrous ; buds ovoid, glabrous, resinous. Leaves 

 ovate or elliptic, sometimes ovate-lanceolate or suborbicular, acute 

 or broadly rounded at the apex, cuneate to truncate at the base, 

 coarsely and acutely few-toothed, lj-2in. or rarely up to 3J in. long, 

 usually 1-1 J in. broad, pubescent when young, soon glabrous, cori- 

 aceous, somewhat glaucous, furnished with 2 glands at the base ; 

 petiole slender, f-lj in. long, soon glabrescent ; stipules linear- 

 filiform, 1| lin. long, quickly deciduous. Male catkins arising from 

 the previous year's branches, leafless at the base, 7|-10 lin. long, 

 8-10-flowered ; rhachis slender, somewhat pilose ; bracts spathulate- 

 cuneate, unequally toothed above, l|-2 lin. long, membranous, 

 quickly deciduous ; pedicels 1 lin. long. Disc membranous, deeply 

 laciniate. Stamens about 30. Female catkins terminating short 

 1-3-leaved shoots arising from the previous year's branches, J-l in. 

 long, 4-14-flowered, lax, at first pubescent on rhachis and pedicels, 

 finally glabrous ; bracts obovate or spathulate, toothed, up to 3 lin. 

 long, membranous, deciduous ; pedicels li-2 lin. long. Disc 

 2-3-partite or divided into filiform segments. Ovary sessile on 

 the disc, ovoid, IJ-lf lin. long, densely grey-tomentose. Style 

 J-j lin. long. Stigmas up to 3.\ lin. long, deeply 2-fid ; lobea 2-3- 

 toothed or -lobed. Capsule ovoid, rounded at the base, subacute, 

 3-6 lin. long, verruculose, shortly pubescent, 2-4-valved. — Stapf in 

 Hook. Ic. PI. t, 3050. P. eufhratica, subsp. DenhcmUiorum, Engl. 



