May, 1922] 
RAINES — VEGETATIVE VIGOR OF THE HOST 
227 
of sowing, setting out of doors to be inoculated, and of concluding the experi- 
ment were the same as in experiment I described above. The results are 
shown in table 7. 
Table 7 
Group 
No. of 
Variables 
No. of 
Plants to a 
3-inch Pot 
Mean 
Dry Weight 
of Top of 
Plant 
in Mg. 
Mean No. of 
Pustules 
per Ave. Unit 
Area of Total 
Leaf Surface 
Mean No. of 
Pustules 
per Ave. Unit 
Area of most Severely 
Infected Leaf 
a 
25 
5 
96 
1.6 
4.1 
b 
20 
2 
264 
1.7 
4.8 
c 
25 
I 
407 
2.0 
5.2 
Experiment III 
120 plants were. grown in 4J-inch pots, divided into four groups on the 
basis of the number of plants grown to a pot. Soil, method of seeding, and 
dates of sowing, of setting out-doors to be inoculated, and of concluding the 
experiment were the same as in experiment I. Results are given in table 8. 
Table 8 
Group 
No. of 
Variables 
No. of 
Plants to a 
4^-inch Pot 
Mean 
Dry Weight 
of Top 
of Plant 
in Mg. 
Mean No. of 
Pustules 
per Ave. Unit 
Area of Total 
Leaf Surface 
Mean No, of 
Pustules 
per Ave. Unit 
Area of most Severely 
Infected Leaf 
a 
50 
10 
161 
1-5 
3-6 
b 
25 
5 
352 
2.4 
6.4 
c 
20 
2 
661 
2.7 
6.5 
d 
25 
I 
976 
2.5 
6.2 
Experiment IV 
600 oat plants were grown in 4J-inch pots, 5 plants to a pot; 15 grains 
being planted in each pot in the first place, and the young seedlings thinned 
out to the desired number. The plants were divided into six groups of 
100 individuals each on the basis of soil composition and treatment, as 
follows: 
Group A : Soil composed of sand only. 
Group B: Soil a mixture of i sand and i garden loam. 
Group C: Soil a mixture of ^ sand and ^ garden loam. 
Group D: Soil the same mixture as in Group C. In addition, KCl at the rate of 350 
pounds to the 6-inch acre of 2,000,000 pounds was intimately mixed with the soil. 
Group E: Soil the same mixture as in Group C. In addition, acid phosphate at the 
rate of 750 pounds to the acre was intimately mixed with the soil. 
Group F: Soil the same mixture as in Group C. In addition, sodium nitrate at the 
rate of 500 pounds to the acre was intimately mixed with the soil. 
Seed was sown July 11, 1920. On July 24, July 31, and August 7 the 
plants of groups D, E, and F had additional quantities of fertilizer applied 
