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 suhject 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 GeofFroy Saint Hilaire, Dean Herbert, Professor 

 Grant, Yon Buch, and some others, had expressed their belief 

 that species arose as simple varieties, and that the species of 

 each genus w^ere 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 ^^ddely distinct 

 types as ^\Tens, 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 



