PLATE XXXVII. BLACK WALNUT. 



1. Branch with developing leaves and (s) three solitary catkins of staminate flowers and (p) 



a spike with three pistillate flowers, x *. 



2. A staminate flower, slightly enlarged. 



3. A pistillate flower, slightly enlarged. 



4. A branch with a mature leaf and fruit, x \. 



5. A winter twig, x J. 



6. Longitudinal section of twig showing chambered pith, enlarged. 



7. Section of twig showing superposed and gaping buds, and leaf-scars with 3 clusters of bundle- 



scars and notched upper surface, slightly enlarged. 



8. A nut with husk removed, x J. 



3. Terminal section of winter twig showing leaf-scar and terminal bud with bud-scales, slightly 

 enlarged. 



