PLATE 6 



EXPLANATIOX OF FIGURES 



19 Culture Y, small tube culture, about 137th generation, April 22, 1914 

 Animal in ascending phase of endomixis. Four micronuclei and four macro- 

 nuclear anlagen present. Numerous chromatin bodies in all stages of degene- 

 ration. 



20 and 21 Culture Y, small tube culture, about S2d generation, April 1, 1914. 

 Animals in ascending phase. Two micronuclei and four anlagen are present. 



22 Culture Y, small tube culture, about 82d generation, April 1, 1914. Animal 

 in the ascending phase, showing one anlage. 



23 Culture Y, small tube culture, about 82d generation, \\n'i\ 1. 1914. Para- 

 maecium cell immediatelj^ after undergoing endomixis. 



94 



