2IO 



EDWIN J. COHX. 



which has stood over eggs combines both the effects of an acid, 

 (aggregation) and also an alkali (agglutination) on the sperma- 

 tozoa" .(Lillie, F. R., 1913, p. 549). The acidity is due to the 

 carbon dioxide that the eggs give forth into the sea water together 

 with any other substances that they may secrete. This carbon 

 dioxide may be removed, and the hydrogen ion concentration of 

 the "egg water" decreased. In that case the ability of the "egg 

 water" to preserve the life of the sperm is much decreased, but is 

 still greater than is that of sea water of exactly the same hydrogen 

 ion concentration. An experiment comparing the effects of egg 

 waters and of sea waters of different hydrogen ion concentrations 

 illustrates this relationship. 



TABLE XVI. 



THE EFFECT OF "Ecc WATER" AT DIFFERENT HYDROGEN ION CONCENTRATIONS 

 UPON THE LENGTH OF LIFE OF SPERMATOZOA. 



Experiment 2/7.' 



That the ability of "egg water" to preserve the life of sper- 

 matozoa is greater than is that of sea water of exactly the same 

 hydrogen ion concentration is probably in large measure due to 



1 Preparation of egg water: 3 c.c. of eggs that had been strained into sea water 

 at 10 A.M. were allowed to stand in 75 c.c. of sea water until 12.30 P.M. 70 c.c. 

 of the supernatent fluid were then decanted and divided into two 35 c.c. solutions. 

 The hydrogen potential was 7.5, which corresponds to a COs tension of 1.14 mm. 

 The CO? tension of the one solution was slightly decreased by. passing room air 

 through it until the hydrogen potential was about 7.65 and the CO 2 tension 0.85 mm. 



