Dec. 10, 1917 Breeding Sweet Corn Resistant to the Corn Earworm 553 
Table II. —Measurement of plant characters at Chula Vista, Cal., in 1915 
Progeny. 
Damage. 
Number of larvae. 
Damage per larva. 
Prolongation. 
First 
ears. 
Second 
ears. 
First 
ears. 
Second 
ears. 
First 
ears. 
Second 
ears. 
First 
ears. 
Second 
ears. 
Phi 18. 
2. i±o. 3 
3 - i±o-3 
1.3±o. 1 
i.4±o. 1 
1.7±o. 3 
2. i±o. 2 
9.8±o. 6 
9.9±0.4 
Phi 19. 
2. 7 ± *3 
i.6± .2 
i.6± .2 
I. 2± .1 
i- 7 ± .3 
i- 3 ± -2 
9 * 7 ± *5 
10.9± -5 
Phl20. 
3*3± *6 
i.gdh .4 
1. 7 ± .2 
I. 2± .1 
2.o± .5 
l-s± *3 
9.8± .6 
9.8± .8 
Phi2i. 
2 -S± *3 
i.6± .2 
i.8± .2 
i-S± *i 
I* 4± .2 
1. I± .2 
9 * 7 ± -2 
9* 8± .5 
Phl22. 
2. 2± .2 
i- 4 ± *3 
l- 4± .1 
i- 3 ± * 1 
I*S± * 2 
I. I± . 2 
II.2± .3 
11.6± .8 
Phi 23. 
I.8± .3 
i-s=t .3 
i- 3 ± -i 
i- 3 ± 
I- 4 ± -9 
I. 2± .2 
8 - 3 ± -4 
8 . 7 ± -5 
Phi24. 
• 8± . 2 
i* 9 ± -5 
1.1± .1 
• 8± .1 
. 7 ± . 2 
2 . 3 ± .8 
I 3 -i± *6 
11.9± *8 
Phi25. 
5 * 9 ± -8 
4- 6± .8 
2. 2± .1 
2-0± .2 
2.8± .4 
2 - 3 ± .4 
9 * 7 ± -5 
8.i± .8 
Phi26. 
3 -i± *3 
4 * 4 ± -7 
2. I± • I 
I.8± .3 
1. 5± .2 
a* 4 ± -5 
6.s± -4 
7 * 8 ± .9 
Phi27.. 
3 * 3 ± -5 
4 * 3 ± *4 
I. 9± .2 
2. I± .1 
i.8± .3 
2. id: .2 
6 . o± . 7 
S-2± .4 
Phi28. 
5* o± .8 
3 -i± *3 
2. I± .1 
I.8± .2 
2 < 4 ± .4 
I* 7 ± -3 
12. s± .6 
ii- 9 ± *7 
Ph.129. 
5.3± 1.1 
4.4± *8 
2-3± .2 
1. 7± *2 
2-3± -5 
2-6± .5 
7 * 7 ± 
10.3± *7 
Phi 3 o. 
3 -i± .4 
2. 7 ± -3 
1. 7 ± .2 
1. 9 ± .2 
I- 9 ± *4 
I. 4 ± *2 
8. 9 ± -5 
8.4± .4 
Phi3i. 
3 - 8 ± .4 
2 - 4 ± *3 
1.9± .1 
x.5± -I 
2.o± .2 
1 I.6± .2 
7 * 3 ± *5 
10. i± .6 
Progeny. 
length of 
ear, 
first ears. 
Number 
of husks, 
first ears. 
Number of layers. 
Days to 
silking, 
first ears. 
Husk leaves. 
Number 
of rows, 
first ears. 
First 
ears. 
Second 
ears. 
First 
ears. 
Second 
ears. 
Phri8. 
13-1 ±0.3 
12. 7±o. 3 
10.7dbo. 3 
io.o±o. 2 
98±i 
2.8±o. 3 
3.3±o. 2 
14. o±o. 2 
Phng. 
i 4 * 7 ± -3 
I 3 * 3 ± .4 
10. o± .3 
10. 4 ± *3 
108 ±1 
. 6± .1 
1. S± .2 
iS*o± .3 
Phi2o. 4 ... 
i 4 - 3 =b -5 
16. 4 ± .7 
11.6± .4 
i2- a± .4 
H 3 ±a 
2-2± .4 
2. 7db .3 
16. 7± .4 
Phi2i. 
14- 3 ± -3 
12.3± .4 
8.8± .4 
7 - 9 ± -3 
107 ± 1 
4 * 3 ± *3 
4* 8± .4 
12.4± .2 
Phl22. 
IS* 8 ± .3 
14* i± .3 
10 . 9 ± .2 
12. 2± .3 
io7±i 
* 4 ± -I 
. 9± • 2 
13* odh .2 
Phi23. 
15 * 4 ± -3 
12. 4 ± .3 
10. 6± .4 
10.3± .2 
105 ± 1 
1* 8± .3 
2.3d: .2 
13 * 2 ± .3 
Phi 24. 
IS* 3 ± .4 
13* 7 ± -4 
11. 6± .5 
10. 9 ± -3 
III i 2 
• 3 ± -2 
I. 2± .2 
17 * I± *4 
PI1125. 
IS* 6± .6 
10. i± .4 
8 - 7 ± .3 
9 * 2 ± .9 
96 ± 2 
i.i± -3 
i*o± .3 
14 * 8 ± .3 
PI1126. 
iS*i± -5 
12.8± .4 
IO. 2± .4 
12. i± . 7 
II 5 ±I 
i.8± .3 
i.6± .4 
17 * S± *5 
Phi27. 
11. 9 ± *6 
*10.8± .6 
7 * 3 ± *2 
7 *i± -5 
104 ±3 
l- 4 ± -4 
3 - 7 ± *5 
13* .4 
Phi 28. 
I 2 - 3 ± *4 
11. 7 ± .6 
7 * 8 ± .5 
8 * 4 ± -3 
I07±2 
i- 4 ± -4 
2.8± .4 
14* 5 ± .2 
Phi29. 
14. 7± .8 
iS-od: .4 
10. o± . 4 
9 * 3 ± -5 
92 i 4 
•7± -4 
i.6± .2 
I 5 * 3 ± *5 
Phi30. 
14 * 3 ± *3 
14. 7 ± -6 
10. o± .2 
9 * 4 ± -2 
90 ± I 
1. 2± .2 
3 * 9 ± -3 
14 * 7 ± -3 
Phi 3 i. 
14* o± .5 
12.8± .6 
9 -i± *3 
9 * 4 ± -3 
103 ±2 
I. 2± .1 
3 * o± .3 
13* l± • 2 
ANALYSIS OF RESULTS IN 1915 
The first step in analyzing the results was to determine whether the 
several rows showed real differences in the amount of damage inflicted 
by the com earworm. If significant differences were not developed, it 
would hardly be worth while to proceed with selection. 
The average damage for the different rows is shown in columns 2 and 3, 
Table II, together with the probable errors. It will be seen that some 
rows are damaged much more than others, and a consideration of the 
probable error shows that many of these differences may not be ascribed 
to chance. An analysis of the first, or upper ears, for which the data are 
more complete, shows that the row with the greatest amount of damage, 
Phi25, was damaged seven and one-half times as much as Phi24, which 
was the least affected. 
It was thought possible that the degree of damage of the different rows 
might be influenced by their position in the field. The infestation might 
come from one side of the field and the rows nearest its source thus be more 
severely damaged. The arrangement of the progenies in the table cor¬ 
responds with that in the field, and no general trend is apparent. It hap- 
