STUDIES IN THE PHYSIOLOGY OF SPERMATOZOA. 



I8 3 



production is divided by the concentration of spermatozoa in the 

 suspension, the carbon dioxide production per unit concentration 

 of sperm is obtained. 



The relative carbon dioxide production of sperm suspensions 

 of different concentrations is reported in Table IV. 



TABLE IV. 



TOTAL CARBON DIOXIDE PRODUCTION OF SPERM SUSPENSIONS. 



It is apparent in the most concentrated suspensions that sea 

 water that is more acid than Ph 7.6 destroys spermatozoa, and 

 causes their death before they have been able to expend all their 

 available energy (see p. 192). A post-lethal increase in acidity 

 occurs in such suspensions. McClendon has evidently made 

 similar observations regarding marine invertebrates, for he says: 

 " It would be of little advantage " to determine the carbon dioxide 

 concentrations in sea water more acid than Ph 7.6 " unless it is 

 first absolutely established that the abnormal Ph does not make 

 the organisms physiologically abnormal and that oxygen is still 

 present in the water ): (McClendon, Gault, and Mulholland, 



I9I7. P- 33)- 



In the less concentrated suspensions which more closely 

 simulate normal conditions it will be seen that spermatozoa 

 that live for longer periods of time produce no more carbon 

 dioxide than spermatozoa that live for only 4 hours. In fact 

 the total carbon dioxide production of spermatozoa is an approx- 

 imate constant. Using the carbon dioxide production as the 

 criterion it must be concluded that the activity of spermatozoa 

 and therefore the life of spermatozoa is limited. 



An analysis of the length of life of spermatozoa is essentially, 

 therefore, an analysis of the rate of activity of spermatozoa under 

 varying environmental conditions. 



