1 82 



EDWIN J. COHN. 



calculation of the carbon dioxide produced by spermatozoa in 

 the above experiment, an increase in carbon dioxide tension (as 

 measured by change in hydrogen potential) may be considered 

 as an increase in free carbonic acid. 



TABLE II. 



HYDROGEN POTENTIALS OF SPERM SUSPENSIONS. 



TABLE III. 



LENGTH OF LIFE OF SPERM SUSPENSIONS. 



The hydrogen potential of sperm suspensions of different con- 

 centrations at different times has been reported (Table II.). 

 The total carbon dioxide production of each sperm suspension 

 is equal to the difference between the carbon dioxide concentra- 

 tion of the sea water at the beginning of the experiment and at 

 the time of the death of spermatozoa. If the total carbon dioxide 



