326 ROBERT T. HANCE 



13. Conjugation is believed to be caused by the concentration 

 of katabolic products in the environment. 



14. It may be said that a potentiahty for extra contractile 

 vacuoles rather than for a definite number of the organs is 

 passed on from generation to generation and that this potentiality 

 if effected by various conditions during the life time of the 

 individual. 



15. Selection has no effect in raising or lowering the vacuole 

 number. 



16. The location of the vacuoles in the parent has an imme- 

 diate but temporary effect on the number possessed by the 

 offspring. 



17. Conjugation has no effect upon this new character. 



