Black Cottonwood 



a. Leaf and bud, x 1/2- 



b. Fruit (capsule), x 1. 



c. d, e. Staminate flower. 



c. Fringed scale, x 2. 



d. Stamens on disc, x 2. 



e. Single stamen, x 4. 



f. g, h. Pistillate flower (after Longyear). 



f. Single flower, x 2. 



g. Cross section of ovary with stigmas attached, 

 h. Fringed scale, x 2. 



Balsam Poplar 



(a) Twig and bud, x i/^; (b) Leaf, x i/^. 



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