TRANSACTIONS OF SECTION D. 
~I 
cr 
“I 
Section D.—ZOOLOGY. 
PRESIDENT OF THE SEcTION—ADAM SxEDewicr, M.A., F.R.S. 
THURSDAY, SEPTEMBER 14. 
The President delivered the following Address : 
Variation and some Phenomena connected with Reproduction and Sex. 
Iw the following address an attempt is made to treat the facts of variation and 
heredity without any theoretical preconceptions, The ground covered has already 
been made familiar to us by the writings of Darwin, Spencer, Galton, Weismann, 
Romanes, and others. I have not thought it advisable to discuss the theories of 
my predecessors, not from a want of appreciation of their value, but because I was 
anxious to look at the facts themselves and to submit them to an examination 
which should be as free as possible from all theoretical bias. 
Zoology is the science which deals with animals. Knowledge regarding 
animals is, for convenience of study, classified into several main branches, amongst 
the most important of which may be mentioned: (1) the study of structure; 
(2) the study of the functions of the parts or organs; (3) the arrangement of 
animals in a system of classification; (4) the past history of animals; (5) the 
relations of animals to their environment; (6) the distribution of animals on the 
earth’s surface. That part of the Science of Zoology which deals with the func- 
tions of organs, particularly of the organs of the higher animals, is frequently 
spoken of as Physiology, and separated more or less sharply from the rest of 
Zoology under that heading. So strong is the line of cleavage between the work 
of the Physiologist and that of other Zoologists, that this Association has thought 
it advisable to establish a special Section for the discussion of physiological subjects, 
leaving the rest of Zoology to the consideration of the old-established Section, D. 
In calling attention to this fact, I do not for one moment wish to question the 
advisability of the course of action which the Association has taken. ‘The Science 
of Physiology in its modern aspects includes a vast body of facts of great import-_ 
ance and great interest which no doubt require separate treatment. But what I 
do wish to point out is that it is quite impossible for us here to abrogate all our 
functions as physiologists. Some of the most important problems of the physio- 
logical side of Zoology still remain within the purview of this Section. 
For instance, the important and far-reaching problems connected with repro- 
duction and variation are very largely left to this Section, and that large group 
of intricate and almost entirely physiological phenomena connected with the 
adaptations of organisms to their environment are dealt with almost exclusively 
here. Indeed, we may go further, and say that apart altogether from practical 
questions of convenience, which make it desirable to separate a part of physio- 
