218 



A. RICHARDS AND DONNELL J. GOOD. 



of the number of extra sperm in the sections studied are presented 



in Table VI. 



TABLE VI. 



Fertilization, of course, is not simply a selection by the egg 

 of one sperm nucleus out of several, for if that were the case it 

 would follow that the increase in the number of sperm to enter 

 the egg w T ould insure a higher percentage of fertilizations. There 

 is no definite relation between the number of eggs fertilized and 

 the number with more than one sperm. 63 has the greatest 

 number of extra sperm, and is also the highest in number de- 

 veloping; C3, however, is next in number of extra sperm, but 

 the percentage of the eggs in development is below the control. 

 These results show, since columns one and two of this table are 

 inconsistent with each other, that at least one other factor (and, 

 of course, many factors) are involved in fertilization which play 

 no part in polyspermy. In the latter case the factors which 

 cause the entrance of the sperm are the ones involved. 



In interpretating the data collected in Table VI. care must be 

 exercised. In the first place it is not possible to control the 

 concentration of the sperm so that relatively many more may 

 not have been added to C3 eggs, for example, than to 03. It 

 is also possible that one set may have been handled more than 

 another, although precautions were taken to eliminate these 

 sources of confusion. Previous investigators have found a great 

 deal of variation in the responses of different lots of Cumin gia 

 sperm and eggs during development, and the factors governing 

 the behavior of any given lot are rather elusive and uncertain. 

 It has already been pointed out in this paper that these experi- 

 ments should be carefully repeated before a final acceptance of 

 the interpretations here given. 



1 Number of eggs counted was too small to permit an entirely trustworthy 

 observation as to polyspermy. 



