PLEA FOR SYSTEMATIC ATTENTION TO AQUATIC BIOLOGY. 141
ecological problems connected with the larger organisms which
cannot be solved without reference to the microscopic forms upon
which they ultimately depend, and there are also those cases of
field phenomena dealt with in my previous address, which are
entirely due to microscopic organisms and often necessitate, for
their explanation, a knowledge of even the minutest forms living
in water. And, lastly, if it is still objected that, after all, micro-
scopical work is not "field" work, it may be remarked that it
could be made so, as it would be quite possible (given certain
facilities, which, as will be suggested later, it should be the am-
bition of a Field Club to provide) to take our microscopes into
the field and to do most of the work of identification of micro-
scopic organisms on the spot. Altogether, therefore, I think
there is no doubt that all aquatic organisms, without limit of
size, ought to be included in Field Club work. This ex cathedra
pronouncement will, I hope, stimulate those of our members who
possess microscopes, but who have not hitherto thought of using
them for this purpose, and those who are thinking of buying
microscopes, to take up the study of one or more groups of the
smaller forms of aquatic life.
But, although the conclusion has been reached that all aquatic
organisms come within the sphere of Field Club work, the question
remains whether we should or should not regard the ascertain-
ment of all kinds of knowledge about them as part of our duty.
My opinion on this matter is that a Field Club may very well
limit itself to two lines of work, namely, the recording of all
the species occurring within its area and the accumulation of
facts concerning their distribution, their habits, and their re-
lations to their environment, i.e. concerning their ecology. The
elucidation of their cytology, histology, embryology, physiology
(in the narrower sense), genetics, etc., scarcely seems to come
within a Field Club's range, although such knowledge when
obtained by others may sometimes prove very helpful in solving
ecological problems.
We now come to the second reason why aquatic plants and
animals have received such a comparatively small amount of
attention at the hands of Field Clubs and Natural History Socie-
ties generally, namely, that the number and importance of the
problems relating to aquatic biology are not very well known.
It would probably be within the mark to say that not ten per