4 1 8 Salicinea Populus. 



are confined to the northern hemisphere. The generic name 

 is of classical origin. 



1. P. tremula. Aspen. An indigenous tree with glabrous 

 buds, pubescent shoots, orbicular-cordate entire or angularly 

 toothed leaves glabrous or pubescent beneath, on long slender 

 laterally compressed petioles. Scales of the rather small catkins 

 ciliate and deeply cut. Stamens about 8. This tree rarely 

 exceeds 50 feet in height, and is remarkable for the almost 

 perpetual quivering motion of the leaves. There is a good 

 weeping variety. 



P. tremuloldes, the American Aspen, is an allied species 

 with roundish-cordate sharp-pointed minutely regularly-toothed 

 leaves. P. Grceca, a slight variety of the foregoing, or perhaps 

 the selfsame thing, is represented in gardens by a weeping form. 



2. P. alba, syn. P. nivea, etc. Abele. A large fast-growing 

 tree with glabrous buds, pubescent shoots, ovate-cordate or del- 

 toid lobed and toothed leaves densely clothed with a cottony 

 down on the lower surface, and long slender petioles. Scales 

 of the catkins ciliate. This is very rare in a wild state, and 

 perhaps not truly indigenous. P. canescens, the Grey Poplar, 

 is a variety with smaller rarely lobed leaves having a greyish 

 tomentum. 



3. P. nlgra. Black Poplar. A fast-growing spreading tree 

 from 50 to 80 feet high with glabrous shoots and glutinous 

 buds. Leaves triangular-ovate, acuminate, serrate, rounded 

 at the base, silky beneath when young ; petiole slender, com- 

 pressed. A native of Europe and North Asia, now much 

 planted in this country. There is a narrow-leaved variety 

 called salicifolia. 



4. P.pyramidalis, syn. P.fastigiata, and P. dilatata. Lom- 

 bardy Poplar. This is very distinct in habit, and easily recog- 

 nised from all other Poplars by its slender erect branches ; but 

 it is nevertheless considered to be a form of the same species as 

 the last. In aspect it is distinct from all other deciduous trees, 

 approaching the close perpendicular growth of the Cypresses. 

 It attains a height of 100 to 150 feet, and is found wild in 

 Southern Europe and the Himalaya mountains. 



5. P. balsamifera. Balsam Poplar, Tacamahac. This is the 

 most commonly planted of the North American species, and 

 resembles P. nlgra in foliage, but the branches are round, 

 not angular, and the bark more furrowed. The leaves too 

 are quite glabrous, strictly ovate-acuminate, with a rounded 



