1897 | RELATION OF NUTRIENT SALTS TO TURGOR 413 
the leaves and younger growing stems removed, and the stems 
and roots separated and bottled. The average turgor at the 
time was: 
In K solution: roots, 1.9%; stems, 3.6%. 
In Na solution: roots, 1.6% ; stems, 2.9%. 
The excess of turgor in the K plants was then about 0.3% 
in the roots, and 0.7% in the stems. Abundant starch was 
present in all the stems of both cultures. By throwing away 
the leaves and youngest internodes, and separating the stems 
and roots, material was obtained for each analysis whose turgor 
was known and uniform. Seedlings of Zea Mays were grown in 
the same way from April 10 until June 12. Two of the K and 
several of the Na plants were then dead. The roots, especially 
of the latter, were in bad condition, while those grown with K 
were very thrifty. All dead parts and the blades of the leaves 
were removed, and the stems and roots separated and bottled. 
The average turgor was: 
In K solution : roots, 2.2%; stems, 3.6%. 
In Na solution: roots, 1.8%; stems, 2.0%. 
Excess of K over that in Na solution: roots, 0.4%; stems, 1.6%. 
As soon as the material from each culture had been gath- 
ered, it was corked tightly in a bottle to prevent egress or 
ingress of watery vapor, and heated to 120°C. in the autoclave.™® 
It was then cooled and all the sap immediately pressed out, 
filtered, and measured. When the sap did not exceed 20°, it 
was all used for analysis. The analysis consisted in oxidizing 
and removing all organic matter by repeated boiling to dryness 
with HNO, and HNO,+HCI; filtering and washing residue 
until no more Cl is dissolved ; addition of NH,OH, which 
caused no cloudiness; removal of Mg and any other heavy 
metals by excess of BaOH ; removal of Ba and Ca by precipita- 
tion with (NH,),CO,; evaporation to dryness and heating to a 
white heat ; and cooling and weighing. The residue should be 
entirely soluble KCl and NaCl. For the sake of certainty it 
** For justification of killing the plants, see deVries, loc. cit. 
