6 
DARWINISM 
CHAP. 
nature and origin of species. They render it clear that, 
notwithstanding the vast knowledge and ingenious reasoning 
of Lamarck, and the more general exposition of the subject by 
the author of the Vestiges of Creation, the first step had not 
been taken towards a satisfactory explanation of the deriva¬ 
tion of any one species from any other. Such eminent 
naturalists as Geoftroy Saint Hilaire, Dean Herbei’t, Professor 
Grant, Yon Buch, and some others, had expressed their belief 
that species arose as simple varieties, and that the species of 
each genus were all descended from a common ancestor; but 
none of them gave a clue as to the law or the method by 
which the change had been effected. This was still “ the great 
mystery.” As to the further question — how far this common 
descent could be carried; whether distinct families, such as 
crows and thrushes, could possibly have descended from each 
other; or, whether all birds, including such widely distinct 
types as wrens, eagles, ostriches, and ducks, could all be the 
modified descendants of a common ancestor; or, still further, 
whether mammalia, birds, reptiles, and fishes, could all have 
had a common origin ;—these questions had hardly come up 
for discussion at all, for it was felt that, while the very first 
step along the road of “ transmutation of species ” (as it was 
then called) had not been made, it was quite useless to 
speculate as to how far it might be possible to travel in the 
same direction, or where the road would ultimately lead to. 
The Problem before Darwin. 
It is clear, then, that what was understood by the “ origin 
or the “transmutation” of species before Darwin’s work 
appeared, was the comparatively simple question whether the 
allied species of each genus had or had not been derived from 
one another and, remotely, from some common ancestor, by 
the ordinary method of reproduction and by means of laws 
and conditions still in action and capable of being thoroughly 
investigated. If any naturalist had been asked at that day 
whether, supposing it to be clearly shown that all the different 
species of each genus had been derived from some one 
ancestral species, and that a full and complete explanation 
were to be given of how each minute difference in form, 
colour, or structure might have originated, and how the 
