The Regional Adaptation of Corn in X eh rash a 
31 
greater for Kimball County corn. Based on Richardson County 
corn as 100 per cent, the relative number of stomata per square 
millimeter of epidermis, length of stoma, and length and width 
of epidermal cells of Kimball County corn were respectively 
114, 90, 94, and 95 per cent. Similar comparisons between 
other counties may be made by a study of the tables. Xo adap- 
tive structural differences are to be observed. 
Fig. 11 — Microphotograph of corn epidermis, showing epidermal cells, stomata, 
and stomatal apertures. Enlarged 116 diameters. 
With the counties grouped into eastern, central, and western 
Xebraska, (Table 16), and the regional data based on eastern 
Xebraska as 100 per cent, we find that (1) the respective relative 
leaf thicknesses are, 100, 104, and 101; (2) thickness of upper 
epidermis, 100, 100, and 99; (3) lower epidermis, 100, 102, and 
102; (4) number of vascular bundles in one centimeter of cross 
section, 100, 94, and 98; (5) average number of stomata per square 
millimeter epidermis, 100, 112, and 114; (6) average length of 
stomata, 100, 9T, and 90; (T) average length of epidermal cell, 
100, 83, and 87 ; and (8) average width of epidermal cell, 100, 
98, and 99. The data suggest that while there is marked adapt- 
ation in morjDhological characters, there is no corresponding 
