244 DIOECIA—OCTANDRIA. Popuhis. 



P. n. 1634 /3. Hall. Hist. v. 2. 303. 



In wet turfy meadows, near rivers, or on dry elevated heatlis, in a 

 light loamy soil. 



Frequent in Norfolk, as on Wells heath, and other places near 

 Holkham. Mr. Croive. Also about Seething. 



Tree. March. 



Root creeping full as extensively as the last. Tree tall and hand- 

 some, with more upright and com\)act branches ; the bark smooth, 

 of a beautiful grey silvery hue. Leaves rounder, more conspi- 

 cuously 3-ribbed, less deeply or acutely lobed ; downy beneath, 

 but chiefly greyish, not so white or cottony j sometimes smooth. 

 Catkins all cylindrical, pendulous, about 2 inches long ; distin- 

 guished essentially from the foregoing, as Mr. Crowe first dis- 

 covered, by the stigmas, which are 8, spreading in two opposite 

 directions. The scales of the fertile catkins are also more deeply 

 and regularly cut. Mr. Crowe was very instrumental in bring- 

 ing this tree into notice in Norfolk. He observed it to be of 

 slower growth than P. alba, with which many British^ as well as 

 foreign, botanists have, from time to time, confounded it, The 

 wood, though, till lately, but litle used or distinguished, is much 

 firmer than that of any other British Poplar, making as good 

 floors as the best Norway Fir in appearance, and having more- 

 over this valuable property, that it will not, like any resinous 

 wood, readily take fire. 



3. P. tremula. Aspen, or Trembling Poplar. 



Leaves nearly orbicular, toothed ; smooth on both sides. 

 Footstalks compressed. Young branches hairy. Stig- 

 mas four, erect, auricled at the base. 



P. tremula. Linn. Sp. PL 1464. mild. i;.4.803. Ft. Br. 1081. 



Engl. Bot. V. 27. t. 1 909. Hook. Scot. 289. Bauh. Pin. 429. 

 P. n. 1 633. Hall. Hist. v.2. 303. 

 P. Lybica. Raii Syn. 446. Ger. Em. 1487./. Lob. Ic. v. 2. 194./. 



Bauh. Hist. v. I.p.2. 163./. Matth. Valgr.v. 1. 125./. Comer. 



EjDit.er.f. Dod.Pempt.836.f. Dalech. Hist.87.f. 

 P. nigra. Trag.Hist. 1083./. 



In moist woods, or in dry gravelly lanes and pastures occasionally. 



Tree. March, April. 



A lofty round-headed tree, with creeping roots, the suckers from 

 which, as well as the young branches, are clothed with brown, 

 prominent hairs j being sometimes hoary, but not cottony. 

 Leaves roundish with a little point, smooth on both sides, 3- 

 ribbed like the last, blundy toothed, somewhat wavy, often 

 shorter than their/oo^s^a/Zc^, which, being vertically compressed, 

 counteract the ordinary undulating motion of the leaves in the 

 wind, and cause them to quiver with the slightest breeze ; whence 



