[macallum] semi-centennial of the origin of species 179 



the " Vestiges of Creation," which appeared in 1843 and which at once 

 attracted attention and criticism. The doctrine began to appear in a 

 more or less inchoate i'onn in the scientific contributions. It was dimly 

 foreshadowed in Huxley's ^Medusa paper published in 1849, and it was 

 as dimly conceived in Lyell's " Principles of Geology," a copy of which 

 was Darwin's companion on the voyage of the Beagle. It was, further, a 

 time when men were turning away from the discussions of empty ques- 

 tions to think of what lay under the surface of things. The period which 

 produced the Bridgewater Treatises and the Oxford Movement had repre- 

 sentatives of a widely different line of thought who cast about for solu- 

 tions of the problems of the world about them. In some cases the two 

 lines of thought were combined, as for example in Faraday and Gosse. 

 This alone shows that the time was ripening for a great event, and the 

 fact tliat the maturation took such a long time, and yet was of such an 

 inevitable character, indicates as clearly that the doctrine of evolution is 

 of psychological as well as of biological application. 



It may be of interest to consider Avhat would have been the history 

 of thougl'.t during tlie last fifty years had Darwin's energies and powers 

 of scientific analysis been directed along some other line or lines. In 

 that case the question would arise ; Would the present form of the the- 

 ory of evolution even in its main outlines now obtain ? To this anyone 

 who is conversant with the biological sciences would answer at once in 

 the negative. Though the concept of evolution, dimly conceived, was 

 " in the air " long before the " Origin of Species " appeared, it was but 

 slowly pervading men's minds, and without the contribution of Darwin 

 it would even now be but a formless idea and a theory. The biologists 

 of the last half of the nineteenth century would have accumulated facts 

 of the greatest value as bearing on the concept of evolution. They would 

 have ascertained, as they did, tliat sexual fertilization involving curious 

 cellular processes is the same in the vegetable kingdom as in the animal. 

 They would further have established, as has been done, that cell division 

 with its intricate phenomena of karyokinesis is in its fundamental char- 

 acters the same in the two kingdoms. They would also have gathered 

 evidence to show that the characters of a species except in certain cases, 

 numerous enough but still limited, are not fixed, unchanging. Indeed 

 they would have discovered thousands of facts whose significance is not 

 now dwelt on simply because they now fall in their place under the great 

 generalization of Darwin, but which in the absence of such an explana- 

 tion would unmistakably point to some gi'eat evolutionary process. It 

 may well be doubted, however, whether the resulting generalization would 

 have been the theory of evolution as Darwin formulated it and as it ob- 

 tains to-day. With the accumulation of a countless number of facts 



