556 IOWA ACADEMY OF SCIENCE 



ABIES AMABILIS Forbes. White Fir. 



Leaves flat, edges turned up, % inch to 1% inches long. 



Resin ducts lateral, touching epidermis on ventral side, lined 

 with two layers of unlignified cells. 



\ ascular bundles surrounded by a sheath of large, round, loosely 

 joined cells, xylem bundles small, separated by a band of 2 

 to 3 rows of lignified cells ; a group of large cells below phloem 

 lignified. 



Hypodermal cells present around entire periphery except along 

 bands of stomata. Walls of these cells very thick and lig- 

 nified; the inner walls of the epidermis lignified. 



Stomata on lower surface, 6 to 8 rows each side of midrib. 





Material from Jamaica Plains, Massachusetts. 



Plate LVL 



Figure 1. — Section of leaf of Abies amabilis. 



Figure 2. — Section through epidermis and stomata of leaf of 

 A, amabilis. 



Figure 3. — Section through resin duct of leaf of A. amabilis. 



Figure 4. — Section through vascular cylinder of leaf of A. 

 amabilis. 



