The Regional Adaptation of Corn in Nebraska 23 
readily visible by giving relative rather than actual figures. In 
this table the ratios are based upon the measurments for 
Richardson County corn as 100 per cent. Richardson County, 
being situated in the extreme southeastern part of the State, has 
normally the longest growing season, highest temperature, and 
greatest precipitation in the State. 
By comparing the results for Richardson and Kimball 
Counties the reaction of corn types adapted to the two most 
extreme environments may be observed. Based on Richardson 
County corn measurments as 100 per cent, relative values for 
Kimball County were as follows: (1) Height of stalk, 60; 
(2) height of ear. 30; (3) leaf area, 37; (4) stover weight, 
41: (5) ear weight, 28; (6) total dry matter, 33; (7) grain 
weight. 25; (8) shelling per cent, 89; (9) leaf area per gram dry 
matter. 108; (10) ear length, 67; (11) ear circumference, 80; 
(12) kernel length, 76; (13) kernel width, 106; and (14) 
kernel weight, 58. Other counties may be compared in a 
similar manner. With some irregularities which are due per- 
haps in part to low frequency of plants studied, the data, for the 
various counties suggest that the more adverse the conditions, 
the more dwarfish is the growth habit of adapted types of corn. 
With the twelve counties under observation, grouped into 
three State regions from east to west (Table 11), the same prin- 
ciples are brought out. Based on eastern Nebraska measurements 
as 100 per cent, relative values for eastern, central and western 
Nebraska were respectively as follows: (1) Height of stalk, 100, 
78, and 68: (2) height of ear, 100, 66. and 40; (3) leaf area, 
100. 67. and 44; (4) stover weight, 100, 74, and 50; (5) ear 
weight. 100, 67. and 39; (6) total dry matter, 100, 70, and 44; 
(7) grain weight, 100. 63, and 35; (8) shelling per cent, 100, 95, 
and 89; (9) leaf area per gram dry matter, 100, 95 and 98; (10) 
ear length. 100. 90, and 79; (11) ear circumference, 100, 94, 
and 84: (12) kernel length. 100, 93. and 84: (13) kernel width, 
100. 103. and 101: (14) kernel weight. 100, 85, and 61. 
HISTOLOGICAL CHARACTERS 
METHODS OF STUDY 
Since the leaf is the seat of food synthesis and of trans- 
piration, it would appear that the most important special his- 
tological adaptations, if any, would occur there. Therefore, 
rather detailed microscopic leaf studies were made for all the 
plants harvested in seven of the counties previously reported. 
At the time of measuring the leaf area, about two weeks 
after tasseling, a leaf sample for sectioning was taken, by means 
