The Experimental Method II 
hard to draw, and since I shall not hesitate at times to enter 
upon the physiological side of many problems, I have chosen 
the somewhat broader title of Experimental Zodlogy to include 
the subjects to be treated. 
The principal topics to be discussed fall under the following 
six headings : — 
I. Experimental Study of Evolution. 
II. Experimental Study of Growth. 
JII. Experimental Studies in Grafting. 
IV. Experimental Studies of the Influence of the Environ- 
ment on the Life-cycle. 
V. Experimental Study of the Determination of Sex. 
VI. Experimental Study of the Secondary Sexual Characters. 
