428 
ALFRED DACHNOWSKI 
depression in the developmental reactions. In the one case both the 
release of energy and the accumulation of food material are stimulated 
in the presence of these salts, while in the other case metabolic reac- 
tions and the process of translocation of food constituents are con- 
siderably retarded. No relationship to transpiration is apparent. 
Where the selective action of the salts favors metabolism and growth 
and the leaf surface increases, transpiration is consequently greater 
also. The relationship, however, is only approximately so. The 
absorption of water and the absorption of salts are not identical 
processes (4). 
7. In table XII are shown in a similar way the comparative effects 
of the presence of equimolecular concentrations of salts in an alkaline 
solution. In almost all cases, the amount of water retained and the 
actual gain in the green weight of plants is larger than that in distilled 
water. But when compared with the corresponding solution of KOH 
n/800 lacking any one of these salts the great difference in the amounts 
induced through the action of electrolytes and non-electrolytes is 
readily noted. It is apparent that at the same concentration of 
alkali the sulfate of calcium is more effective in increasing the water 
content of the plants than the sulfate of sodium. The order in which 
the anions are grouping themselves is not as readily made out as in 
the case of the acid solutions. The causes for these changes, here as 
in several of the examples cited above, are undoubtedly several in 
kind, and largely due to the chemical changes taking place within the 
cells and tissues of the plants. There is no difficulty in recognizing 
the following order in which the kations are effective, that one pro- 
ducing the greatest reaction being given first: Ca, Na; the position 
of K is somewhat variable. Again no relationship to the amount 
of water transpired is noticeable ; the selective activity of the salts 
and their beneficial or injurious effect is independent of the solute. 
This lack of relationship is most marked upon comparison with the 
non-electrolytes, and upon observing the reaction of the various 
salt solutions on the metabolism of the plants. The greatest dif- 
ference between the quantity of water retained and the actual gain in 
the green weight of the plants is obtained in CaCl2; the least differ- 
ence is found in KCl. Of extreme importance in this connection is 
the gain in the weight of plants over and above the amount of water 
retained by them in the alkaline solutions of glycocoll and sucrose. 
There seems scarcely any doubt that the organic compounds accele- 
rate both the hydrolytic and the synthetic reactions. 
