536 IOWA ACADEMY OF SCIENCE 



PICEA BREWERIANA Wats. Weeping Spruce. 



Leaf flat, 3-sided. (The lower side is the flat side), % i ncn to 

 l*/o inches long. 



Resin ducts 2, large, lateral, touching ventral epidermis, lined 

 with 2 layers of flat cells, inner layer lignified. 



Vascular bundle — Xylem bundles very small, separated by 2 rows 

 of irregular, lignified cells. Phloem band large, cells of pith 

 largely lignified, cells of bundle sheath lignified where joined 

 to each other. 



Hypodermal cells very pronounced around entire periphery ex- 

 cept on upper side along bands of stomata, 2 rows deep, 3 

 rows deep at angles. 



Epidermis cutinized in thick outer walls, inner wall lignified. 



Stomata in broad bands on upper surface only, 4 to 5 rows in 

 each band. 



Parenchyma deeply corrugated. 



Material from State House grounds, Sacramento, California. 



Plate XLVI. 

 Figure 1. — Section of leaf of P. breweriana. 



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

 P. breweriana. 



Figure 3. — Section through resin duct of leaf of P. brew- 

 eriana. 



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

 breweriana. 



