138 



WILLOWS AND POPLARS 



[CH. 



A& 



d;.. 



f.0'^' 



iSSiSi 



oMm 



N 



a- 

 S 



Fig. 39. Flowers of Willows and Poplars. A, male flower of Sali.r 

 fragilis; B, of S. pentandra; C, of S. purpurea; D, oi Populus tremula. 



