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ceptible growth occurred in its presence, but a i per cent, solu- 

 tion caused pitchers to wither in six days, while a 2 per cent, 

 solution made them brown and dry in three days. Both young 

 and matured pitchers were used for this experiment but the re- 

 sults were the same in either case, 



Sachs's Nutrient Solution. — A nutrient solution such as that 

 commonly used as a water culture for flowering plants (per 6,000 

 c,c. : CaN03, 6.0 gr.; KNO3, 1,5 gr,; K,HPO„ 1.5 gr,; MgSO,, 

 1.5 gr,; FeSO^, a trace) was placed in pitchers, and caused them 

 to begin to decay within a few days, the tissues being entirely 

 dead in from two to three weeks. 



Liebig's Meat Extract. — The effect of a stimulant was tested 

 by means of a dilute solution of Liebig's meat extract. Bacteria 

 and infusoria developed in great numbers, however, and the 

 pitcher began to wither in less than a week, becoming entirely 

 decayed in about two weeks. 



Milk. — A solution of milk, one drop in 10 c.c. of distilled 

 water, which was neutral to litmus when placed in the pitcher, 

 gave no odor and no acid reaction with litmus at the end of six 

 days. When the concentration was doubled the solution became 

 acid and the pitcher decayed almost completely in two weeks, 

 A solution of milk, 20 per cent, by volume in distilled water, 

 coagulated and became unpleasant in odor, within two days. It 

 was inferred that the pitcher gave out an alkaline substance 

 which reacted with the acid produced in the very dilute solution 

 of milk but was not sufficient to neutralize the solutions of 

 greater strength. There was nothing to indicate that the milk 

 fat or protein was digested. 



Distilled Water. — For comparison with the preceding solu- 

 tions, distilled water was kept in certain pitchers for a period of 

 about five weeks, by means of frequent renewals. There was no 

 change in the external appearance of the pitchers, which is in- 

 teresting from the fact that a concentrated solution of sucrose 

 was equally harmless, so that the tissue of the pitcher is able to 

 adapt itself to solutions widely different in osmotic strength. 



The following solutions were also placed in the pitchers of 

 Nepenthes distillatoria, the plants being kept in the propagating 



