170 



TREES OF MINNESOTA. 



Plate 15. Juglans nigra. Black Walnut. 



1. Flowering branch, one-half natural size. 2. Staminate flower before an- 

 thesis, enlarged. 3. Staminate flower, enlarged. 4. Perianth of staminate 

 flower, displayed, enlarged. 5. Stamen, enlarged. 6. Pistillate flower, natural 

 size. 7. Longitudinal section of pistillate flower, natural size. 8. Leaf, re- 

 duced. 9. Winter branchlet, one-half natural size. 10. Mature fruit, one-half 

 natural size. 



