STUDIES IN THE PHYSIOLOGY OF SPERMATOZOA. 



179 



tion" (Gemmill, J. F., 1900, p. 171). J An experiment similar to 

 those performed by Gemmill is reported (Table I., Experiment 

 28). The "term of vitality" of spermatozoa was determined 

 by testing their fertilizing power. As in Gemmill's experiments 

 the sperm in the most concentrated suspensions lived for the 



longest time. 



TABLE I. 



EXPERIMENT 28. 



The Length of Life, as Measured by the Fertilizing Power, of Sperm Suspensions of 



Different Concentration? 



The measurement of the total carbon dioxide production in 

 sperm suspensions of different concentrations, which will now 

 be reported, has however made untenable the position of Gem- 

 mill that the "exhaustion of energy" is not sufficient to account 

 for the "loss of vitality of spermatozoa." 



The Measurement of the Total Carbon Dioxide Production of 

 Sperm Suspensions of Different Concentration. 



The hydrogen potential of sperm suspensions of varying con- 

 centration was measured as a function of time. 



In measuring the hydrogen potential of sperm suspensions 



1 The so-called "artificial nutrition" was brought about by adding beef broth 

 to sea water. This increases the hydrogen ion concentration of the suspension 

 and decreases the activity of spermatozoa. The evidence for these statements 

 will be found in another place in this paper. 



- The sea water in this experiment was sterilized in order to prevent the bacterial 

 contamination which otherwise occurs when sperm suspensions are kept for so 

 long a time (Gorham, F. R., and Tower, R. W., 1902). Erlenmeyer flasks were used 

 in the experiment. On the third day suspension i was still relatively free from 

 bacteria. The spermatozoa appeared healthy and were not motile. 



