141 



dialjsing sac of collodion. The ox^'gen of llie siirrouiidiug liquid 

 passes through these sacs without difficulty, as could be shown in 

 preliminary experiments, but oidj a very small quantity of organic 

 sul)stances passed through so that the method of Winki.kf{ for the 

 «letermination of 0, dissolved in water, could be used with a slight 

 correction. This very useful method of Winki-kk can only be used 

 in the absence of organic substances in the liquid or after a cor- 

 rection has been made *). 



This dialysing sac was put into a bottle, which was completely 

 filled with Fühnkk's solution of known 0, content. After some time 

 (1—2 hours) a certain quantity of the contents of the bottle was 

 again secured for a Winkler's determination of its 0^ percentage. 



In order to stimulate the organ during its stay in the liquid, two 

 silver electrodes wei'e tied to the organ. Organ and electrodes were 

 then put into the dialysing sac and immersed into the liquid. The 

 organ was stimulated dii'ectly once every 5 sec. 



The results are given in the following table: 



TABLE I. 



1) See Henze Abderh, Handb. der Biochem. Arbeitsmeth. Ulg p. 1067. 



