1920] 
DUGGAR—H-ION CONCENTRATION AND NUTRIENT SOLUTIONS 21 
TABLE VIII 
(Series 3, Wheat) 
SALT REQUIREMENTS AND H-ION CONCENTRATION IN RELATION TO GROWTH; 
SOLUTIONS A, B, AND C; RENEWAL AFTER A TEN-DAY INTERVAL 
Total | Total | Greatest Pu 
No. rire . wt. ldry wt.| length 
menees | (gms.) | (gms.)| (em.) | Initial [End 1st per.|End 2nd per. 
1 |AwO 2.55 10.482 12.40 4.8 4.6 4.8 
2 |Aw9/IOK, 5.04 /0.765 15.29 5.3 5.6 6.3 
3 |Aw4/5K 5.50 0.812 14.07 5.5 5.2 5.9 
4 |Aw3/5K 5.52 |0.748 13.76 6.0 5.6 6.1 
5 |Aw1/2K 5.53 0.849 12.23 6.1 5.5 6.4 
6 |Aw3/IOK| 1.06 /0.262 10.64 6.4 6.0 61 
7 |Awh/Al 2.52 10.506 13.61 3.6 3.8 4.9 
8 |AwAI 4.40 /0.668 13.52 5.3 5.5 6.1 
9 |BwO 7.02 11.079 20.12 5.9 7.6 7.4 
10 |2(BwO) 7.90 |1.094 19.11 5.8 7.6 8.0 
11 |BwK; 2.82 10.470 14.42 re 8.2 8.5 
12 |BwCa 5.12 10.789 17.14 7.6 7.8 8.8 
13 [BwAl 10.30 11.622 26.65 LX 7.0 8.0 
14 |CwO 4.95 |0.707 14.10 4.8 5.9 6.7 
15 |CwNH 5.57 10.858 16.15 4.3 4.6 5.8 
16 |CwGC 5.50 ¡0.846 16.91 6.7 1.0 8.8 
17 |CwGP 1.70 /10.308 10.77 TL 7.4 4,0 
18 |[Cw /1 7.10 10.995 16.24 5.3 6.2 i. d. 
19 |Cw /2 6.42 10.887 16.62 5.8 6.4 7.6 
20 |Cw /5 5.50 10.778 16.28 6.4 6.8 7.4 
21 |CwAI 6.45 (0.971 14:67 5.4 6.4 7.4 
house, and the cultures were distantly spaced on a lattice table, 
or bench, constructed with the idea of providing for all cultures 
uniform circulation, or conditions favoring uniform water loss. 
The light relations were perhaps somewhat more favorable for 
the group of cultures renewed at four-day intervals. This 
series was begun on May 14. During the first two weeks the 
weather was moderate and cloudy, while during the last week it 
was bright and warm, perhaps too warm for the best growth of 
wheat. While the evaporation from a standardized spherical 
atmometer was low, seldom exceeding 12 gms. per day, during 
the first two weeks it rose to a maximum of 27.8 and 25.4 as a 
record for the two houses on May 31. 
The modification in the A group of cultures in this series con- 
sisted chiefly in the introduction of K;HPO, as a source of part 
