122 FAMILIAR TREES AND THEIR LEAVES. 



P. Alba, var. Nivea 



under side of its leaf, 



which is variously 



shaped according to 



the varieties which 



I have drawn. The 



branches of this tree 



are also downy and 



white when young, and 



its roots are apt to produce 



numerous suckers. Its typical 



form is less grown here than 



the varieties. 



The variety of the white 

 lar which, according to Prof. 

 Bailey, is commonest in this 

 country, is called P. 

 alba, var. nivea.* Its 

 leaves have three or five 

 maplelike divisions, and 

 they are very cottony be- 

 neath. Another variety intro- 

 duced into Europe in 1875, from 

 Turkistan, is called P. alba, var. 

 Bolleana. This tree has a compact- 

 p.Aiba,var.Boiieana. growing habit, something like the 



* Vide The Cultivated Poplars, Bulletin 68, L. H. Bailey. 



