380 



HOYT S. HOPKINS 



TABLE 2 



PARAMECIUM STRAIN 



P. caudatum, 

 IJalll 



P. caudatum, 

 17ain 



(P. aurelia, 2Si 

 added on March 

 31) 



P. caudatum, 



17aIII 

 (P. aurelia, 13a 



added on March 



31) 



DORMANT CULTURE 



March 15, 1919 



March 15, 1919 



March 15, 1919 



DATE renewed; 

 CULTURE MEDIUM 



March 31 (aqueous) 



March 31 (aqueous) 



March 31 (aqueous) 



CONJUGATION IN THE 

 RENEWED CULTURE 



April 10, about 30% 

 April 11, about 20% 



P. caudatum: 

 April 10, about 20% 

 April 11, about 30% 

 P. aurelia: 

 April 12, one pair 



P. caudatum: 

 April 10, casual 



P. aurelia: 

 None 



TABLE 3 



(Each of the seven cultures of Paramecium caudatum Jisted in the first column was 



treated as here indicated) 



