228 



BLACK POPLAR 



and purple-red before anthesis, up to 7 x T2 cm., the 

 J stalked and greenish, up to 10 x O8 1 cm., and in 

 fruit up to nearly 13 14 cm. long. Scales membranous, 

 glabrous, greenish-yellow, cuneiform, cut into long purple 



Fig. 69. a, Black Poplar, Populus nigra ; b, Populus Canadensis, 

 p. 226 (Sc). 



teeth, caducous. Stamens usually about 8 (6 30) with 

 long white filaments and purple anthers, becoming yellow 

 and then black ; scales falling before anthesis. Pollen 

 pale yellow, irregularly polyhedral, warted, 30 40 //,. 



