PLATE XLVII. BLACK BIRCH. 



1. Flowering branch with (s) staminate flowers, (p) pistillate flowers, s i 



2. Branch with mature leaves and three fruiting strobiles, x g. 



3. A winged seed, enlarged. 



4. A strobile scale, enlarged. 



5. Winter branch with partly developed terminal staminate aments, x i. 



6. Section of a winter twig, enlarged. 



