July i, 1921 
Relation of Length of Kernel to Yield of Corn 
435 
Tabl3 XI. —Frequency distribution of ears of various lengths of kernels in the progeny 
of smooth, medium, and rough corn, 1916-1919 
Number of kernels having a length (in inches) of— 
Year and type. 
7/32 
8/32 
9/32 
10/32 
n/32 
j 12/32 
13/32 
14/32 
15/32 
16/32 
17/32 
18/3 
1916: 
Smooth. 
1 
3 
27 
39 
M 3 
28 
Medium. 
7 
Rough. 
1 
3 
17 
27 
70 
105 
128 
48 
56 
6 
5 
1917: 
Smooth. 
2 
6 
14 
44 
84 
166 
88 
57 
18 
7 
2 
2 
Medium. 
6 
18 
6e 
16 
Rough. 
9 
17 
50 
81 
155 
86 
62 
22 
i 7 
1918: 
Smooth. 
7 
17 
35 
83 
113 
195 
94 
59 
26 
5 
1 
Medium. 
15 
12 
18 
37 
74 
182 
95 
65 
49 
16 
2 
1 
Rough. 
13 
5 
15 
41 
35 
145 
63 
75 
4 i 
4 i 
5 
8 
1919: 
Smooth. 
1 
17 
18 
51 
81 
137 
124 
134 
7 i 
54 
16 
1 
Medium. 
2 
1 
17 
36 
58 
120 
133 
M 7 
79 
50 
3 
2 
Rough. 
82 
116 
66 
. 
Four-year average: 
Smooth. 
Medium. 
Rough. 
Num- 
- bcr 
of 
2 ears. 
Aver¬ 
age 
length 
of 
kernel. 
504 
459 
469 
Inches. 
o. .5 S3 
.407 
.411 
490 
506 
530 
• 37 i 
.385 
•375 
639 
565 
488 
•358 
•379 
•385 
705 
649 
692 
. 400 
• 409 
•425 
•378 
•395 
• 399 
TRANSMISSION OF INDENTATION IN THE PROGENY OF SMOOTH, 
MEDIUM, AND ROUGH TYPES OF CORN 
The number of ears of each type in the progeny of each type is shown 
in Table XII. The results are illustrated in figure 1 and Plates 84 to 87. 
The data show that there was a marked tendency for the smooth, medium, 
600 
600 
^600 
I „ 
If 
1 
SMR 
m l III Hi fn 
SMR SMR 
< 5 MR SMR 
7 T~I 
m 
SMR 
SMRISMR SMR 
p 
iffh 
SMR SMR SMR 
1 
1 
SMOOTH 
MEDIUM ROUGH -SMOOTH 
MEDIUM ROUGH 
SMOOTH 'MEDIUM ROUGH SMOOTH MEDIUM ROUGH 
/S/6 
/ 9/7 
/ 9 /S 
/ 9 /S 
Fig. i.—T ransmission of the character of indentation in the progeny of continuously selected smooth, 
medium, and rough typesof corn. The columns show the number ofearsof the respective types in the prog¬ 
eny of smooth-, medium-, and rough-dented Commercial White com for each season. 
and rough types to transmit their respective type characters to the 
progeny each season. This fact is most apparent in the smooth type. 
For each successive season the proportion of corn of the smooth type in 
the progeny increased over that for the preceding season. There was 
very little variation in the medium type except for the dry season of 1918. 
The percentage of ears of the smooth type that season was greatly 
increased, apparently because of the effect of drought on the development 
of the ears. This also occurred in 1919, but not to the same extent. 
