17, 6 Trelease: Salt Requirements of Wheat Plants 585 
Dry weights.—The actual dry weights of tops and of roots 
for this series are given in Table 15, the weights of the plants 
in each of the duplicate cultures and the average weights being 
shown. The data given in this table have been plotted as 
graphs in fig. 10. In these graphs abscissas represent concen- 
tration, in terms of osmotic pressure in atmospheres, and ordi- 
nates represent yields in grams. The heavy line is the graph 
for the T2R4C2 cultures, the light line for the T1R1C1 cultures, 
the dotted line for the T7R1C1 cultures, and the broken line for 
the R5C24 cultures. 
TABLE 15.—Dry weights. of tops and roots of wheat; for series IV, conducted 
from January 23 to February 24, 1917. 
Tops (6 plants). Roots (6 plants). 
Osmotic 
Culture No. concen- 
tration. A. B. |Average.| A. B. | Average. 
Aim. g. * g. g 0. g g. 
7.09 0.675 0. 582 0. 629 0.210 0.240) 0.225 
5.5 0.728 0.696 | . 0.712 0.280 0.271} 0.276 
4.5 0.788 | * 0,750 0.769 0.305 0.301 | 0.308 
3.5 0.769 0. 760 0. 765 0.297 0.266 | 0,282 
Lalee: gence ine scemea ee: 2.5 0.767 0.699 0. 738 0.271 0.258 0.265 
1.6 0. 712 0. 687 0.700 | 0.255 0.269 | 0.262 
1.0 0. 828 0.600 0.714 0.217 0.216 | 0.217 
0.5 0.613 0. 602 0. 608 0. 226 0.234} 0.280 
7.0 0.709 0. 705 0.707} 0.208 0.166 | 0.185 
5.5 0.771 0.740 0. 756 0. 205 0.196 | 0.201 
4.5 0.823 0.762 0.798 0.230} 0.238) 0,282 
3.5 0. 823 0.771 0.797 0.236 0.249} 0.248 
TINS seen eee 2.5 0.789 0.768 0.776 0.241 0.257 | 0.249 
1.6 0.747 0. 722 0.735! 0.257| 0.262] 0.260 
1.0 0. 650 0.611 0.631 0.204 0.208! 0.206 
0.5 0.642 0.610 0. 626 0.210 0.207} 0.209 
7.0 0.776 0.762} 0.769 0.271 0.278 | 0,272 
5.5] - 0.851 0.790 0. 821 0.814} 0.297] 0.806 
= 4.5 0. 922 0. 885 0.904 0.329| 0.304| 0.817 
3.5 1. 056 1.008 1.080 0. 871 0.350} 0.361 
i emarigal oceat ca 2.5 1.164 1.070 1.117 0. 373 0.356 | 0.365 
1.6 1.165 1.188 1.152 0. 367 0.379 | 0.378 
1.0 0. 994 0. 900 0.947 0.305 0. 284 0.295 
0.5 0. 973 0. 878 0. 926 0. 268 0.3382 | 0.300 
7.0| 0.723| 0,642| 0.688, 0.226] o.221| 0.224 
55| 0.819| 0.752| 0.786| 0.272| 0.266| 0.269 
45| 0.968| 0.912| 0.938] 0.824| 0.305| 0.315 
35| 1.01¢| 0.933| 0.975| 0.304| 0.346| 0.925 
R5C2} ----.-.---. ---------- o5| Liev] 1.123| 1.125] 0.350/ 0.388] 0.869 
16| 1160} 1.1483] 1152] 0.985] 0.845| 0.865 
1.0] 1.018} 0.985} 0.999) 0.814] ¢.298} 0.804 
0.5| 0.908} 0.875| 0.892) O.271| O.274} O278 
