xvi] METHODS OF RESEARCH 265 



mental science to pass into other hands. But zoology and 

 physiology are essentially one, and each suffers from the 

 division, inevitable though it was, that has come between 

 them. If cytology is to avoid a similar misfortune, its stu- 

 dents must keep in view the need for both the descriptive 

 and comparative and the experimental methods, and re- 

 member that the bio-chemist and physicist are studying 

 with flask and test-tube the same problems that they them- 

 selves are attacking with microscope and microtome. 



