198 Nebraska Agricultural Exp. Station, Research Bui. 6. 
DESCRIPTION OF PLATE IV. 
Fig. 1. — Three-plane view of leaf. X 233. Diagrammatic. 
A, cross section of leaf. 
a, upper epidermis, b, lower epidermis, c, chlorophyll-bearing 
tissue, d, phloem of vascular strand, e, xylem of vascular 
strand. /, chlorophyll-bearing bundle sheath, g, cross section 
of stoma, h, air chamber beneath stoma. 
B, longitudinal section of leaf. 
a, upper epidermis, b, lower epidermis, c, chlorophyll-bearing 
tissue, d, phloem of vascular strand, e, xylem of vascular 
strand. /, longitudinal section of stoma, g, air chamber beneath 
stoma, h, epidermal hair. 
C, inside surface view of lower epidermis, 
a, epidermal cell with nucleus, b, stoma. 
Fig. 2. — Two-plane views of bundle of stem. X 233. 
A, cross section. 
a, side of bundle toward outside of stem, b, side of bundle 
toward inside of stem, c, large pitted vessel, d, supportive 
tissue, e, air cavity. /, parenchyma cells of pith, g, compressed 
protophloem. 
B, longitudinal section. 
a, parenchyma cells of pith, b, phloem cells of bundle, c, air 
space seen in longitudinal section, d, xylem elements of bundle. 
