It)2 



EDWIN J. COHN. 



are instantly agglutinated. If sea water is about Ph 7.6, sper- 

 matozoa are inactive. Sea water that is much more acid than 

 Ph 7.6 not only tends to inactivate, but also to destroy sperma- 

 tozoa and the more so the higher the hydrogen ion concentra- 

 tion and the longer the sperm are subjected to these acidities. 



y.o />* 

 84- . 

 8-0 Ph. 

 7.2. , 



72. 84 



//v MINUTES 



DIAGRAM III. 



In sea water that is less acid than Ph 7.6 spermatozoa live the 

 longer the higher the hydrogen ion concentration. The more 

 inactive the spermatozoa the more slowly their "fertilizing 

 power" diminishes when they are transferred to sea water where 

 they are reactivated. 



VII. THE RELATION BETWEEN THE ACTIVITY AND THE "FER- 

 TILIZING POWER" OF SPERMATOZOA. 



"Within a wide limit of egg-concentration the important 

 factors in fertilizing power of sperm suspensions are: (i) concen- 

 tration, (2) time" (Lillie, F. R., 1915, p. 246). The results of 

 this investigation confirm this general conclusion of Lillie's, and 



