tr3 BOTANICAL GAZETTE [AUGUST 
the establishment of a balanced solution, with other work now con- 
templated by the writer, will form the subject of another article. 
SERIES V. POTASSIUM CHLORID vs. CALCIUM CHLORID 
In these experiments the technique was somewhat different from 
the foregoing. All the salts were used at a concentration of 0.35 m? 
and mixed with each other in various proportions in Erlenmeyer 
flasks of 250°° capacity. Two or three liters each of KCI and CaCl, 
solution of the concentration above noted were made up to contain 
Kang, . ©.75 per cent. peptone.’ In each flask of the 
Zong, first half of the series were placed 100°° of the 
KCl-peptone solution. To no. 1x nothing was 
added; to the others up to no. 6 there were 
Yémg. added respectively 5, 10, 25, 50, and 100° of the 
CaCl,-peptone solution. Then beginning at 
the other end of the series each flask received 
Shelia too°° of the CaCl,-peptone solution. Flask no. 
11. contained this alone; to the preceding ones 
in order were added respectively 5, 10, 25; 
te 50, and 100°° KCl-peptone solution, the 
. two halves of the series meeting 
in no. 6, as shown in 
go the curve (fig. 2) and 
table V, at the combi- 
PS, BDU PMNs Ae Cal 
AGT SAG Oe e ee" Joe a 5, mire 
nation of 100°¢ of each solution. In order to keep the volume the same 
in all cultures they were thoroughly mixed, and enough solution draw? 
off with the pipette, where additions were made, to make all the culture 
2 This concentration was chosen because it was about the concentration of NaCl 
in sea water of San Francisco Bay. 
3 This concentration of peptone was used in all the experiments with binary 
solutions. 
ee er eke ee ee 
a 
A 
