402 



WILSON GEE. 



no fertilizations were secured; in the others, only two and these 

 were developing normally at the end of the sixth day. 



There seems to be very plainly exhibited in this experiment 

 an eliminating action of the alcohol on the spermatozoa. The 

 treatment was of sufficient length to kill out all of the weaker 

 ones, and the stronger ones fertilized the eggs with resulting 

 normal individuals. 



(e) Effects of Methylene Blue Solution on Eggs Prior to Fertiliza- 

 tion. As stated earlier in this paper, the results of the Hertwigs 

 ('13) on the treatment of the sperm with methylene blue seem 

 somewhat contradictory in nature. Treatmentof the spermatozoa 

 of Gobius jozo for one hour in 0.02 per cent, and o.i per cent, solu- 

 tions showed a decidedly injurious effect when used to fertilize 

 the eggs of the same species of fish. When the spermatozoa were 

 treated for forty-five minutes with the o.i per cent, solution and 

 used to fertilize the eggs of another fish, Crenilabrus pavo, the 

 resulting development showed no effect of this treatment. 



In the light of the experiments reported in the first section of 

 this paper, it appeared that the discrepancy might be explained 

 as due to the difference in effect upon the eggs of the two fishes 

 of the methylene blue in the sperm suspension used to fertilize 



the eggs of the fish. 



TABLE XL 



RESULTS OF TREATING EGGS OF Fundulus heteroclitus WITH SOLUTIONS OF METHY- 

 LENE BLUE FOR FIFTEEN MINUTES PRIOR TO FERTILIZATION. 



Accordingly an experiment was planned to test the plausibility 

 of this view when applied to the eggs of Fundulus heteroclitus. 

 The results of this experiment are given in an accompanying 

 table (see Table XL). While the matter was not exhaustively 



