408 PROCEEDINGS OF SECTION D. 
On the other hand, physiologists working at the circulation of 
the blood, the optical properties of the eye, the changes occurring 
to food under the influence of the digestive juices, the relationship 
between the chemical changes occurring in muscle and the work 
and heat given out, were equally confident that the only inter- 
pretation of these phenomena was to be found in the laws of 
necessity regulating the relationships of matter as known to 
chemistry and physics. 
These two ways of viewing biology were, indeed, irreconcilable, 
and necessitated those who studied function parting company ; 
nor can we wonder that they had little sympatby with each other’s 
point of view. 
SKETCH OF THE PROGRESS OF ANATOMY AND PHYSIOLOGY AFTER 
THEIR SEPARATION UNTIL THE PRESENT TIME, 
T shall now attempt to indicate what each of the great divisions 
of biology has been doing during the last fifty years, and the 
points to which each has separately arrived, by different methods 
and along different lines. I shall not attempt to give a complete 
survey of the work done, but only in the most general way draw 
your attention to the kind of work each division has been doing. 
As regards anatomy in particular, my remarks must be taken as 
a mere impressionist picture, taken from afar and in a dim light, 
for I am not competent to depict anatomical progress or results in 
any detail. 
After the physiologists had started off with the notion of inter- 
preting vital activities in terms of the simpler laws of chemistry 
and physics, the anatomists continued to gather in facts concerning 
the structure of all kinds of animals. They systematised their 
knowledge by means of the leading principle of homology. 
When in 1859 Darwin’s “ Origin of Species” was published, 
the morphologists had their time ‘Fully occupied for some years, 
until they had verified a system under which they could classify 
all their facts, which was complete in itself, and represented the 
order of the plant and animal world. Obser vations in the domain 
of paleontology and embryology henceforth received a greatly 
increased value. An army of students of comparative embryology 
soon arose, and the one man who stands out most prominently as 
a leader in the development in this direction is Balfour. 
Broadly speaking, up to within recent years, the morphologists 
have been busy discovering new facts, and arranging them in their 
system, until at the present time morphology has come to express 
the study of the formation and structure of animals and plants 
in relation to community of descent. 
They are industriously constructing a huge genealogical tree of 
the organised world, and in this work alone there is room for 
