EFFECTS OF SELECTION ON THE YIELD OF CORN. 
13 
planted in ear rows in 1917. Two plantings were made, the first on 
April 23 and the second on May 11. Desirable ear rows were deter- 
mined on the basis of performance in the earlier planting, and desir- 
able individual plants in homologous rows of the later planting were 
self-pollinated. This method of double planting was very satisfac- 
tory, as the advance information from the first planting eliminated 
much unnecessary hand pollination. Its use has been prohibited 
since 1917 by climatic and soil conditions that prevented the early 
planting. Preliminary selection consequently has been based on 
the appearance of the rows at the time of blossoming, final judgment 
being reserved until autumn. There were 34 ear rows in 1918. 
Some of the selected ears from the 1918 crop were lost during ship- 
ment, and only 20 ear rows were planted in 1919. The numbers of 
ear rows mentioned refer only to those representing continuously 
selfed lines from the original 1916 selection. Other selections that 
have been introduced from time to time need not be considered here. 
Table 3. — Pedigrees of ears representing self -fertilized strains of No. 201 corn planted at 
King, La., in 1920 to obtain crosses for comparison at Burdette, Ark., in 1921, showing 
the relation of such ears to the original cross. 
[Explanation.— In 1914 the Whatley variety was crossed by St. Charles White. In 1915 the Fi cross 
was grown, open fertilized. In 1916 the F 5 cross was grown, and 360 ears were self-fertilized. The subse- 
quent use of pedigree numbers and strain designations is shown in the table.] 
Pedigree numbers, No. 201. 
1920. 
Strain 
desig- 
nations. 
1917 
1918 
1919 
1920 
2 
i 
5 
7 
9 
10 
12 
13 
15 
2-2 
3-1 
5-1 
1- 
9-2 
10-3 
12-1 
13-1 
15-1 
f 2-2-1 
\ 2-2-2 
I 2-2-3 
3-1-1 
) .5-1-1 
!■ 5-1-2 
j 5-1-3 
7-1-1 
/ 7 4-1 
\ 7-4-2 
f 9-2-1 
\ 9-2-2 
I 9-2-3 
I 10-3-1 
\ 10-3-2 
f 12-1-1 
\ 12-1-2 
13-1-3 
J 15-1-1 
\ 15-1-2 
2-2- 1-, 1,2,3 
2-2-2-, 3, 4 
2-2-3-, 3, 4, 5 
3-1-1-, 2, 3, 4 
5-1- 1-, 1, 3, 4 
5-1-2-, 1, 2, 3 
5-1-3-, 1,2 
7-1-1-, 1,2,3 
7-4-1-, 5, 7 
7-4-2-, 1,2, 3, 4, 5, 6 
9-2-1-, 1,2,3 
9-2-2-, 1, 2, 3, 4 
9-2-3-, 1,2,3 
10-3-1-1 
10-3-2-1 
12-1-1-, 2, 3 
12-1-2-, 1, 2 
13-1-3-1 
15-1-1-; l, 2 
15-1-2-, 1, 2, 3, 4 
1 2-2- 
3-1- 
7-1- 
\ 7-4- 
l 9-2- 
}• 10-3- 
\ 12-1- 
13-1- 
} 15-1- 
METHOD OF CROSSING. 
From the 1919 ear-row plat 53 selfed ears were obtained for use 
in crossing and for further breeding operations. The pedigrees of 
these ears and their relation to the original cross, Whatley X St. 
Charles White, are shown in Table 3. Seed was composited to rep- 
resent each of the 10 strains shown under "Strain designations" in 
the table, and a row of each was planted at King. La. 3 in 1020. 
Crosses were made between the strains by hand pollinating, pollen 
