Corn Investigations 
67 
Table 23 . — Comparison of first generation hybrids and their 
pure line parents. Hogue's Yellow Dent low leaf area 
strains. Two-year average , 1915 and 1916. 
Hybrid 
yield 
per acre 
Moisture free weights of inbred parents 
Hybrid 
Ear weight 
Total plant weight 
Female 
Male 
Average 
Female 
Male 
Average 
a) 
Bushels 
(2) 
Grams 
(3) 
Grams 
(4) 
Grams 
(5) 
Grams 
(6) 
Grams 
(7) 
Grams 
(8) 
FIVE HIGHEST YIELDING HYBRIDS 
736 X 754 
72.1 
54.3 
109.3 
81.8 
163.6 
219.7 
191.6 
735 X 736 
71.8 
80.6 
54.3 
67.4 
190.1 
163.6 
176.8 
738 X 735 
70.4 
9.3 
80.6 
44.9 
114.0 
190.1 
152.0 
731 X 739 
72.8 
84.7 
34.2 
59.4 
154.2 
134.5 
144.3 
754 X 738 
74.1 
109.3 
9.3 
59.3 
219.7 
114.0 
166.8 
Average 
72.2 
67.6 
57.5 
62.6 
168.3 
164.4 
166.3 
HYBRIDS INTERMEDIATE IN YIELD 
731 X 736 ..... . 
57.9 
84.7 
54.3 
70.0 
154.2 
163.6 
158.9 
751 X 738 
66.2 
55.7 
9.3 
32.5 
161.3 
114.2 
137.7 
731 X 732 
65.8 
84.7 
20.8 
52.7 
154.2 
133.6 
143.9 
738 X 734 
63.2 
9.3 
35.4 
22.3 
114.2 
125.9 
120.0 
737 X 754 
65.5 
64.0 
109.3 
66.6 
196.5 
219.7 
208.1 
731 X 734 
65.4 
84.7 
35.4 
60.0 
154.2 
125.9 
140.0 
755 X 754 
64.7 
77.0 
109.3 
93.1 
214.4 
219.7 
217.0 
738 X 752 
64.5 
9.3 
56.2 
32.7 
114.2 
203.6 
158.9 
Average 
64.1 
58.7 
53.7 
53.7 
157.9 
163.3 
160.6 
FIVE LOWEST YIELDING HYBRIDS 
738 X 736 
54.9 
9.3 
54.3 
31.8 
114.2 
163.6 
138.9 
734 X 732 
31.8 
35.4 
20.8 
28.1 
125.9 
133.6 
129.7 
748 X 731 
44.8 
42.4 
84.7 
63.5 
186.7 
154.2 
170.4 
756 X 730 
51.9 
29.4 
54.2 
41.8 
125.7 
140.0 
132.8 
733 X 753 
52.4 
18.4 
59.8 
39.1 
116.2 
154.4 
135.3 
Average 
47.2 
27.0 
54.8 
40.9 
133.7 
149.2 
141.4 
These data are compiled from Tables 20 and 21. 
RATE OF GROWTH OF FIRST GENERATION HYBRIDS BETWEEN PURE LINES 
The mature kernels of inbred corn (pure lines) commonly 
weigh less than those of the original heterozygous corn from 
which they are derived. Cross-fertilized kernels borne on 
these pure line plants weigh on an average only about ten 
per cent heavier than selfed kernels. It has been suggested 
that first generation hybrids of pure lines are at a disad- 
