EFFECTS OF ALCOHOL ON GERM CELLS OF FUNDULUS. 395 



with twenty per cent, alcohol for even three minutes and activate 

 a sufficient number to get some eggs fertilized. The small pro- 

 portion which were revived to activity in this way indicated that 

 most of the spermatozoa had been injured to a sufficient degree 

 to cause their death. 



Sea water solutions of alcohol produced very different results. 

 The length of life was much longer in these, but except in rare 

 instances, not a single spermatozoon after having ceased move- 

 ment could be activated with the addition of the alkali solution. 

 The resistance of the spermatozoa from a number of fish to the 

 action of several solutions is given in the accompanying table (see 

 Table V.). It will be observed that only in the highest percen- 



TABLE V. 



LENGTH OF LIFE OF SPERM OF Fundulus IN ONE TENTH OF A CUBIC CENTIMETER 

 OF DISTILLED WATER, SEA WATER, AND GRADES OF ALCOHOL IN SEA WATER.! 



tages is the time element satisfactorily eliminated. In these the 

 greatest length of life is less than the shortest length found in 

 the sea water alone. On this account, it was with these higher 

 percentages that much of the work on the male germ cells was 

 done. 



The factor of dilution is another important one in the length 

 of life of the sperm. A mass of spermatozoa placed in a large 

 quantity of pure sea water became inactive in a very short time. 

 In order to control the effect of dilution, the amount of solution 

 used in these experiments was carefully measured and constant. 



The causes of the inactivity of the sperm in distilled water, 



1 These periods represent the interval between the stripping of the milt from 

 the male and the cessation of movement on the part of every spermatozoon in 

 the dish. Consequently they represent the length of life of the most vigorous 

 sperm in each lot. 



