ACTION OF ALKALIES ON PLANARIA. 



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oxygen concentrations (between 7.0 and 2.0 cc. per liter, at least). 

 The oxygen concentrations employed in the experiments was such 

 (5 to 7 cc. per liter) that there is no possibility that the reduction 

 in oxygen content by the worms during the experiment could have 

 the slightest effect upon the amount of oxygen consumed. 



TABLE I. 



RESULTS OF A TYPICAL EXPERIMENT, SHORT TIME, AT EACH pH USED. 

 Figures represent cc. of oxygen consumed per hour. 



NaOH 



NH 4 OH 



Normal respiration in water. pH 7.6-7.8. 



Respiration in alkaline water. 



Average per cent, of increase of each of above. 



TABLE II. 



AVERAGE PERCENTAGES OF INCREASE AND DECREASE BASED ON TOTAL OF ALL 

 SHORT EXPERIMENTS DONE AT EACH pH. 



Figures are per cent, from the normal. 



NaOH 



NH 4 OH 



Increase and decrease in respiration rate from normal. 



The results of all of the short time experiments are given in 

 graphic form in Fig. i, made from the data given in Table II. 

 The rate of oxygen consumption is given on the ordinate, normal 

 respiration in untreated water being taken as 100, respiration in 



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