992 REPORT—1896. 
SECTION K.—BOTANY. 
PRESIDENT OF THE SectIon.—D. H. Scort, M.A., Ph.D., F.R.S., Honorary 
Keeper of the Jodrell Laboratory, Royal Gardens, Kew, 
THURSDAY, SEPTEMBER li. 
The PresIDENT delivered the following Address :— 
Present Position of Morphological Botany. 
TH object of modern morphological botany (the branch of our science to which 
I propose to limit my remarks) is the accurate comparison of plants, both living 
and extinct, with the object of tracing their real relationships with one another, 
and thus of ultimately constructing a genealogical tree of the vegetable king- 
dom. The problem is thus a purely historical one, and is perfectly distinct 
from any of the questions with which physiology has to do. 
Yet there is a close relation between these two branches of biology; at any 
rate, to those who maintain the Darwinian position. For from that point of view 
we see that all the characters which the morphologist has to compare are, or 
have been, adaptive. Hence it is impossible for the morphologist to ignore the 
functions of those organs of which he is studying the homologies, To those 
who accept the origin of species by variation and natural selection there are no 
such things as morphological characters pure and simple. There are not two 
distinct categories of characters—a morphological and a physiological category— 
for all characters alike are physiological. ‘ According to that theory, every 
organ, every part, colour, and peculiarity of an organism must either be of benefit 
to an organism itself, or have been so to its ancestors. . . . Necessarily, according 
to the theory of natural selection, structures either are present because they are 
selected as useful, or because they are still inherited from ancestors to whom they 
were useful, though no longer useful to the existing representatives of those ancestors.’ ! 
The useful characters may have become fixed in comparatively recent times, or 
a long way back in the past. In the latter case the character in question may 
have become the property of a large group, and thus, as we say, may have become 
morphologically important, 
For instance, parasitic characters, such as the suppression of chlorophyll, are 
equally adaptive in Dodder and in the Fungi. In Dodder, however, such cha- 
racters are of recent origin and of little morphological importance, not hinder- 
ing us from placing the genus in the natural order Conyolvulacee; while in 
Fungi equally adaptive characters have become the common property of a great 
class of plants. 
Then, again, the existence of a definite sporophyte generation, which is the 
great character of all the higher plants, is in certain Fungi inconstant, even among 
members of the same species, 
Although there is no essential difference between adaptive and morphological 
' Lankester, Advancement of Science, p. 307. 
