152 72. SALICACE.E. 



flower. Cap. with long silky footstalks, and a few leafy bracts 

 at the base. 



Frequent. Moist heaths, moors, and sandy places. (B) Sh. 4 5. Fossil 

 marsh ; Campsie hills ; Gourock ; Kilmun ; Cumbrae and Arran. 



11. S. HERBACEA, L. Least-Willow. The smallest British 

 shrub, seldom rising more than 2 3 in. above the surface of the 

 soil. Le. round or oval, finely crenate, shining, smooth, netted 

 with raised veins beneath. Catkins very small. Styles short. 

 Stigmas bifid. Ovaries smooth. 



Frequent. On the tops of our highest mountains, creeping amongst loose 

 stones. (H) Sh. 6. Hills between Lock Eck and Glen Messen. "Ben Varen, 

 Arran," Lands. 



2. POPULUS. Poplar. 



1. P. ALBA, L. Abele, Great White-Poplar. A large tree, 

 with spreading branches, and ash-white bark. Le. orbicular, 

 more or less cordate at the base, sinuate or lobed, covered with 

 white cottony down underneath, young shoots slightly cottony, 

 when old mostly smooth. Catkins sessile, about 2 in. long. 

 Scales cut at the apex. Stigmas 2, bipartite, yellow. Plant 

 throwing up suckers. 



Common. In plantations. (E) T. 34. Stonelaw woods, &c. 



Var. canescens. Le. cottony and grey beneath. Stigmas 3 4- 

 lobed, purple. 



Frequent. In plantations. 



2. P. TREMULA, L. Aspen, Trembling -Poplar. A smaller 

 tree than either of the former, with slender branches, remarkable 

 for the tremulous motion of its le. when scarce a breath of wind 

 is stirring, caused by the long petioles being very much com- 

 pressed on the sides. Le. nearly orbicular, bluntly sinuate, 

 toothed, smooth on both sides, paler underneath. Scales of the 

 catkin deeply-cleft. Stigmas 2, deeply divided, purple. Buds 

 smooth, slightly viscid. 



Frequent. In moist woods. (B) T. 34. Common in Cumbrae and Arran, 

 evidently wild. 



3. P. NIGRA, L. Black Poplar. A very large tree, never 

 throwing up suckers, leaf-buds smooth and viscid. Le. ovato- 

 triangular, acuminate, serrate, smooth on both sides. Petioles 

 laterally compressed. Catkins long, loose. Scales hairy on the 

 tip. Stigmas roundish, 2-lobed. 



Common. In plantations, and on river banks. T. 3. 



Var. fastigiata, is the well-known Lombardy Poplar, having 

 very erect branches, giving an elongated conical form to the tree. 



