MICHIGAN ACADEMY OF SCIENCE. 



81 



155 16!, 171) 



185 195 205 



225 235 245 255 26E 



Fig. 2. Diagrams showing variation in length in control series of Paramecia of selected ancestrj-. 

 gram II, 100 hour series. Diagram III, 200 hour series. Diagram IV, 300 hour series. 



11 



Dia- 



