Bouyoucos, Transpiration of Wheat Seedlings as Affected etc. 
17 
Mention bas been made that tbe sand ° d soil cultures were 
employed, first, to duplicate tbe solution cultures; and secondly, to 
see wbetber tbe different densities of solution vvould affect tbe 
Transpiration of tbe wbeat seedlings in tbese media in tbe same 
Order or in tbe same magnitude as in tbe water cultures. Tbe 
table below gives tbese data. 
Table IX. 
Difference in tbe Transpiration Per Gram of Dry Matter Among Solution, 
Sand and Soil Cultures. 
Density of Solution 
in P. p. m. 
4500 
2250 
750 
376 
187.5 
93.5 
0.0 
Average 
Greater Transpiration per Gram 
of Dry M> _ter in Sand Cultures 
over Water Cultures 
14.6 
10.7 
20.0 
8.9 
— 10.8 
— 21.1 
172.6 
27.8 
Greater Transpiration per Gram 
of Dry Matter in Soil Cultures 
over Water Cultures 
141.1 
169.2 
143.7 
129.2 
146.6 
181.7 
332.1 
177.7 
Tbis table sbows tbe difference in tbe transpiration per gram 
of dry matter between solution and sand cultures and between 
solution and soil cultures, solution cultures being taken as a Standard 
in botb cases. It will be seen tbat tbere is a significant difference 
among tbese comparisons. Botb tbe sand and soil cultures tran- 
spired more per gram of dry matter tban tbe solution culture, and 
tbe soil culture transpired tbe most. Tbe sand and tbe soil cultures 
gave off 27.8 and 177.7 grains of water per gram of dry matter 
respectively, more tban tbe solution culture. Evidently, tbe different 
densities in tbe culture solution diminisbed tbe magnitude of tbe 
transpiration per unit of growth, more tban in tbe sand and soil 
cultures. 
One otber interesting feature tbat may be worked out from 
tables I, II and III, is tbe difference in tbe dry matter produced 
between solution and sand cultures, solution and soil cultures, and 
sand and soil cultures. Tbe fable below gives tbese data. 
. ' Table X. 
Difference in the Dry Matter Produced Among Solution, Sand And Soil Cultures 
Density of So¬ 
lution in P. p. m. 
Greater Growth in 
Greater Growth in 
Greater Growth in 
Solution Cultures Over 
Solution Cultures Over 
Sand Cultures Over 
Sand Cultures 
Soil Cultures 
Soil Cultures 
Grams 
Grams 
Grams 
4500 
— .00331 
—.00355 
—.00024 
2250 
—.00390 
.00071 
.00461 
750 
.00146 
.00658 
.00512 
375 
.00451 
.00683 
.00232 
187.5 
.00435 
.00482 
.00047 
93.5 
.00235 
.00129 
—.00106 
0.0 
—.00152 
—.00255 
—.00103 
Average 
.00056 
.00206 
.00145 
Beihefte Bot. 
Centralbl. Bd. XXIX. 
Abt. I. Heft 1. 
2 
