EFFECTS OF ALCOHOL ON INFUSOKLA. 



97 



is, after being subjected to copper sulphate for twenty-three days, 

 whereas the culture which had never been subjected to alcohol 

 survived under the copper sulphate treatment until discontinued 

 (Fig. 4). A closer analysis of the curves shows that during the 

 earlier periods of the experiment the division rate of the organ- 

 isms treated with 1/2,500 alcohol was somewhat less affected by 

 the copper sulphate treatment than the division rate of the non- 



Fig. 4. Paramecium. Culture I (hay infusion, control) periods 47 through 54 



= continuous line; culture Ic subjected to CuSO^ = line. X = point at 



which culture Ic was discontinued. Other details as in Fig. i. 



alcoholized line, but this was merely temporary. The lines sub- 

 jected to the greater amount of alcohol (Fig. 6), which were 

 averaging a higher rate of division than the lines treated with the 

 less amount (Fig. 5), were more susceptible to copper sulphate 

 from the beginning than either the non-alcoholized line (Fig. 4) 

 or the line on the less amount of alcohol, and finally died out. 



