100 
Scientific Proceedings (43). 
mals and in one animal which received an intravenous infusion of 
dextrose. The results may be briefly summarized as follows: 
The exudate of pulmonary edema contains dextrose or a reducing 
substance. The concentration seems to be in general equal to that 
of the blood. Two hours or longer after an intramuscular injection 
of adrenalin the exudate of the pulmonary edema may contain 
0.5 per cent, and more of dextrose, a quantity, which, at least 
so far, usually slightly exceeded that of the corresponding blood. 
61 (586) 
The effect of culture medium contaminated with the excretion 
products of Paramecium on its rate of reproduction. 
By LORANDE LOSS WOODRUFF. 
[From the Sheffield Biological Laboratory of Yale University.] 
A summary is presented of the initial experiments of a series 
which is planned to elucidate, if possible, some of the complex 
factors at work in a "hay infusion"; for example, such as those 
which determine the inter-dependence of the organisms, their 
sequence, time of appearance, disappearance, etc. The data 
outlined were derived from the study of : (a) the effect of different 
volumes (2, 5, 20 and 40 drops) of culture medium on the rate of 
reproduction of Paramaecium; (b) the effect of changing the culture 
medium daily and on alternate days on the rate of reproduction 
of Paramaecium; and (c) the effect of culture medium, in which 
large numbers of paramaecia have been living, on the rate of re- 
production of Paramaecium. It is believed that the results ob- 
tained justify the following conclusions: 
1. The rate of reproduction of Paramaecium aurelia&vA Para- 
maecium caudatum is influenced by the volume of the culture 
medium, within the limits tested, and the greater the volume the 
more rapid is the rate of division. 
2. Paramaecia excrete substances which are toxic to themselves 
when present in their environment, and these substances are more 
effective when the organisms are confined in limited volumes of 
culture fluid. 
3. The excretion products of paramaecia play an appreciable 
part in determining the period of maximum numbers, rate of 
decline, etc., of this animal in "hay infusions." 
