242 Studies in the Physiologn of Fertilization 



in the fertilizing power of the sperm. The striking point in the results 

 is however that, for each pair of fertilizations, the percentages are 



Time ( 

 mixing € 



Exp. 1. BIc 



Exp. 2. Ajb 



lower with eggs which have been previously treated with "own" sperm 

 than with those not so treated. In most cases, moreover, the cross- 

 fertilization percentages of the former should be still lower than those 

 actually counted and recorded in the Table, since during their stay in 

 "own" sperm-suspension a certain number of the eggs had already been 

 self-fertilized. In order to allow for this factor the proportion of eggs 

 remaining in "own" sperm, which had been self-fertilized, was calculated 

 at the same time as the cross-fertilization percentages were counted. 

 These figures are given in the last column of the Table. In the last 

 fertilization of Exp. 2, the treated eggs show an apparently higher 

 cross-fertilization jDercentage than the untreated ; but on examining 



