The Presidential Address. 
81 
Camels and Hyaenas have been worked out by Professor 
Cope 20 and M. Gaudry 21 respectively. In Palaeontology, as 
in every other branch of Biology, the Darwinian theory has 
in fact become incorporated as a part of common knowledge; 
witness the following extracts from the latest text-book of 
Geology published in this country :—“ It must he conceded 
that on the whole the testimony of the rocks is in favour of 
the doctrine of evolution.” 22 “But to the palaeontologist it 
is a matter of the utmost, importance to feel assured that, 
though he may never he able to trace the missing links in 
the chain of being, the chain has been unbroken and per¬ 
sistent from the beginning of geological time.” 23 “From 
this point of view the investigations of Palaeontological 
Geology are invested with the profoundest interest, for they 
bring before us the history of that living creation of which 
we form a part.” 24 
Returning once again to the principles of the selection 
theory, we see that every modification of an organism implies 
the addition to, or the modification of, some structure or 
function already possessed. It is most essential to hear in 
mind that Darwin’s prime mover, natural selection, acts not 
only upon external characters, but likewise upon internal 
organisation; minute constitutional or physiological deviations 
at present utterly beyond the ken of science, can be seized 
upon and perpetuated by this agency when of any advantage 
to the possessor. The survival of the fittest is utilitarianism 
in excelsis. From the dawn of life upon this earth there must 
thus have been on the whole a tendency for living beings to 
increase in complexity of structure and function,—a tendency 
to a more complete biological division of labour both in indi¬ 
viduals and in races,—a tendency to become more and more 
specialised, or, as it is said, to “advance in organisation.” 
It is almost needless for me to pause here in order to point 
20 Amer. Nat., 1880. 
21 ‘Les enchainements du Monde Animal.’ 
22 Geikie, p. 624. 
23 Ibid., p. 626. 
24 Ibid., p. 627. 
O 
