114 THE WILLOW FAMILY. 



quite at variance with those of its relatives. Of the mature trees the bark 

 divides into long, narrow plates, which at their extremities curve away from 

 the tree, but remain attached at the centres as does the bark of the shell 

 bark hickory. 



P, gajididentdta, large-toothed aspen, as its name would imply, is 

 known by the large, coarse teeth which surround the margins of its broadly 

 ovate and pointed leaves. When young they have on their under surfaces 

 a white tomentum ; but it is the baby leaves which are particularly beautiful, 

 they being on both sides soft and silvery and making the tree appear in 

 early spring as though it were arrayed in woolly white. Although reported 

 to occur in a wild state through the Alleghanies we did not meet with it 

 in our travels. Northward, it is to many a familiar individual. 



In addition to these native species of poplars there are seen through the 

 south these others which have become naturalized. 



P. alba, silver-leaf poplar, which is one of the best known and most grace- 

 ful of the genus. Its young foliage is covered with a thick, white t'omentum 

 which clings always to the undersides of the leaves, and when by the wind 

 these silvery surfaces are turned upward, the people take it as a sign that 

 rain is near. The tree springs up along roads and is abundantly reproduced 

 by suckers that arise from the bases of the older ones, 



P. cdiidicans, balm of Gilead, a tree quite common through the south, 

 was in the beginning planted by residents and has now escaped from cultiva- 

 tion. Its natural home has been pointed out by Professor Bailey to be in 

 the region of the great lakes and in Michigan he reports a number of 

 individuals. 



P, dilatdta, Lombardy poplar, appears an unusually strange figure when 

 seen looming tall and straight on some of the high and remote places in the 

 Alleghanies. Originally it was imported to this country from Italy ; but 

 now so thoroughly naturalized has it become that its perpendicular, distinc- 

 tive manner of growth is perhaps better known than the habit of any one of 

 the native species. In many places, however, where once the trees grew 

 singly they now appear to be sending up numerous shoots from their stolonif- 

 erous roots. 



