Dec, 1922] RUTH EFFECT OF BORDEAUX MIXTURE 
the acetone by washing with water; (4) separation of xanthophyll by 
washing with eighty percent methyl alcohol; (5) removal of acetone and 
methyl alcohol by washing with water, which results in the precipitation 
of the chlorophyll ; (6) removal of the water by means of anhydrous sodium 
sulphate ; (7) removal of the fine precipitate of chlorophyll and its separation 
from carotin by filtering through talc; (8) solution of the precipitated 
chlorophyll in ether and reprecipitation by adding petrol ether ; (9) filtration 
through talc; (10) solution of the precipitate in ether; (11) evaporation 
to dryness. (The processes are described and discussed in detail by Will- 
snatter and StoU, 1913, pp. 132-135.) 
The chlorophyllin solution was made by (i) transferring the pigments 
in a raw eighty-five-percent acetone extract to ether; (2) saponification of 
the two chlorophylls with methyl-alcoholic potash; (3) the separation of 
these products from carotin and xanthophyll by extracting them with 
water. (Willstatter and Stoll have given complete directions for this 
separation, 1913, pp. 81-82.) 
The only modification of the method presented by Willstatter and Stoll 
was the use of comparatively larger quantities of solvent than the small 
quantities of leaf powder called for. The entire amount of leaf powder to 
be standardized was mixed and quartered, and from these portions were 
taken 0.25-gram samples for the preparation of the raw solutions in 85- 
percent acetone, to be used as standards, 10 grams for the isolation of the 
solid chlorophyll mixture, and 2.5-gram samples for the preparation of 
the chlorophyllins. 
The samples used for chlorophyllin preparation were extracted with 85- 
percent acetone and made up to 100 cc. Ten cc. of this were used in the 
succeeding steps. A solution made by diluting the result of the final 
separation to 100 cc. with alcohol was of the proper strength for comparison 
with the standard chlorophyll solution of Willstatter and Stoll. (0.0513 
gram chlorophyll is dissolved and made up to 100 cc. in absolute alcohol. 
For use in the colorimeter 10 cc. are diluted to 200 cc. 1913, p. 81.) 
In making a raw extract for colorimetric comparison a 0.25-gram sample 
was extracted with successive small quantities of 85-percent acetone, which 
were filtered off, combined, and made up to 50 cc. in a graduated flask. 
Portions of approximately 2 cc. were used in the colorimeter. The depth 
of the standard raw acetone extract in the colorimeter was maintained at 
20 mm. 
Variation in Chlorophyll Content with Development 
OF the Primordial Leaves 
Before determining the effect of spraying upon the chlorophyll content, 
it was thought desirable to determine the degree of variation in chlorophyll 
content which took place as the plant grew. Willstatter and Stoll (1915) 
