EXPERIMENTAL ZOOLOGY 
CHAPTER I 
THE EXPERIMENTAL METHOD 
THE study of Zodlogy by experimental methods is not a new 
departure, for the method of experiment has been often applied 
to special zodlogical problems. On the other hand, the recogni- 
tion that only by experimental methods can we hope to place 
the study of Zodlogy on a footing with the sciences of chemistry 
and of physics is a comparatively new conception, and oné that 
is by no means as yet admitted by all zodlogists. I do not wish 
to appear to disparage those studies that deal with the descrip- 
tive and with the historical problems of biology. They also 
offer a wide field for activity, and the more familiar we become 
with the structure and modes of development of animals, so 
much the better can we apply the experimental method. In 
fact, many of the problems of biology only become known to us 
as the result of direct observation. The wider, therefore, our 
general information, the greater the opportunity for experimen- 
tation. 
It is undoubtedly true that many zodlogists who have spent 
their lives in acquiring a broad knowledge of the facts of their 
science fail to make use of their information by testing the very 
problems that their work suggests. This is owing, no doubt, to 
their exclusive interest in the observational and descriptive sides 
of biology, but also in part, I think, to the fact that the experi- 
mental method has not been sufficiently recognized by zodlogists 
as the most important tool of research that scientists employ. 
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