41 8 ALFRED DACHNOWSKI 
different acids and alkalies; there is the analogous lack of relationship 
between concentration and the capacity for water retention: an 
optimal point is reached beyond which a further concentration of the 
acid or alkali is not followed by a greater water content but by a lesser 
one ; the effectiveness of the anion SO4 of the particular acid concerned 
is the same; the increase is greater in alkaline than in equally con- 
centrated acid solutions; the order of the effectiveness of the anions 
of equimolecular salt solutions in an acid medium (table V) is the same 
as that observed in the series above ; and the action of the non-electro- 
lytes is comparatively similar in this regard. 
Important differences, however, exist between the two kinds of 
seeds which are not without their physiological interest. The amount 
of water that may be taken up by corn seeds is rnuch smaller than that 
which can be retained by the seeds of the bush bean. The results for 
the anions of the equinormal acid and alkaline solutions are more 
nearly alike than those for the kations. The general grouping of K 
and Ca for seeds of Zea mats (table VI) is the reverse of that observed 
in Phaseolus muUiflorus, Ca being more active in bringing about an 
increase in the water content than K, and this more than Na. The 
velocity of the reaction is decreased when sodium takes the place of 
calcium. As the increase in weight between Ca and K in these 
experiments is considerable, the difference in the reaction must be 
looked for not in the external conditions of temperature, etc., for they 
were the same, but in the essential differences of the cell constituents 
of the two kinds of seeds and their reactions in these solutions. 
Another point of interest in this connection is the definite and 
distinct decrease in the capacity of corn seeds to absorb and retain 
water with any addition of osmotically equivalent concentrations of 
certain salts (table V). The anions CI and NO3 are again nearly alike 
in the degree of their effectiveness in lowering the water content, 
while the kations Ca and K increase the amount of water retained by 
the seeds. Sucrose shares with the electrolytes Na and K the marked 
power of reducing the water retaining capacity of seeds in an acid 
solution; on the other hand, dextrose and glycocoll produce a definite 
acceleration, but the former more so than the latter when starches 
are affected. 
These results seem to justify the general conclusion that the 
variations in the water content of seeds cannot be brought about solely 
through the concentration of acids or alkalies within the cells and 
