20 , BOTANICAL GAZETTE yoy 
In this sand the very rapid decrease in the force with which 
its particles hold water as moisture content increases stands in 
sharp contrast to the slower decrease in the heavy clay subsoil. 
While the air-dry sand gives the same kind of result as the air-dry 
clay, by the time the sand contains 0.44 per cent of water the 
seeds secure as much water as they do in a molecular solution of 
non-ionizable salts. This indicates a force of 22.4 atmospheres. 
3. Various soil types.—The results obtained with the subsoil of 
the Oswego silt loam and the no. 2/o sand suggested that there 
might be a general relationship between soils and seeds as regards 
the amount of moisture seeds will absorb at the wilting coefficient 
of the soil, whatever value the wilting coefficient might have. To 
clear up this point, the soil types of table II were used. Each soil 
was brought as nearly to the wilting coefficient as possible by 
addition of water. The closeness of the experimental conditions 
to the wilting-coefficient determinations is shown in columns 3 and 4 
of table VIII. 
TABLE VIII 
RELATION OF BY SEEDS 
i Percentage of 
Soil types ieiveconle ©|* -acmiege ot | Pieceniaes 1) Fe 
1. Sand (coarse)........ 0.205 0.73 0.02 0.65 34-44 
ye We ass eg a er 2.536 I12.930.05 12.66 49.02 
3. Sandy loam (very fine) 1.836 8.330.08 48.38 
Ae LOOM 5 ei 2.280 I2.41+0.02 13.30 49.01 
€, iny loam, 2. 3.820 16.120,01 16.01 49.49 
6 2 a pein w knee oe 5.210 16.340.02 17.78 47.31 
Jo PING GONG So is os ne ev ©.750 3.21%0.03 3-19 49.77 
8. Sand (coats) ieee: 0.218 0.83 OI : 40.98 
G heeniir 2.30 10.82+0.06 10.51 50.42 
The percentage of moisture taken up by dry seeds placed in 
each soil is shown in the last column of the table. With the excep- 
tion of the two sands from Yuma, Arizona, which are coarse, the 
results are fairly uniform. In two cases the soils adhered badly 
to the seeds, making accurate work very difficult; but corrections 
were made as carefully as possible. In all the other soils the seeds 
remained clean, or were easily brushed free of adhering particles. 
The average intake for the 7 types, excluding the coarse sands, is 
