Cottonwood 



1. Winter twig, x i. 



2. Leaf, x y 2 . 



3. Staminate flowering branchlet, x x /j. 



4. Staminate flower, enlarged. 



5. Pistillate catkin, x y 2 . 



6. Pistillate flower, enlarged. 



7. Fruit, x y 2 . 



56 



