XCIV PROCEEDINGS OF THE 



their way into public addresses and works in which science is 

 diluted for popular use, even by Fellows of our society, I may per- 

 haps be allowed a few observations on what appears to me to be the 

 present state of the questions he has propounded, and how far their 

 solution has been promoted by his present work. 



It is nearly ten years since the first sketch of his now celebrated 

 theory of Natural Selection was laid before this society, followed 

 early in 1859 by the publication of his ' Origin of Species ; ' it is this 

 day five years that, on the occasion of calling your attention to the 

 reception which his views had met with from the scientific woild, I 

 observed that the tide of opinion among philosophical naturalists 

 appeared to be fast setting in favour of the hypotheses he advanced. 

 From such a review as I have been able to make of the current 

 biological literature, it appears to me that the current has continued 

 to flow in the same direction. There is scarcely a work or a paper 

 on general biological subjects in which Darwinism is not more or 

 less discussed, tiie name being adopted (at least in America and 

 Germany) as no longer conveying a sneer. Eminent naturalists, 

 who were still reluctant to abandon long-cherished theories, and 

 hesitated to declare themselves openlj', have now boldly adopted 

 Darwinian views ; from Sir Charles Lyell, who had formerly relied 

 on the multiple fixity of species, we have, in the recent tenth edition 

 of his ' Principles of Geology,' a most admirable summary of the 

 theory of derivative origin and of its bearing on the geological his- 

 tory of the globe ; profound thinkers, especially in Germany and 

 in this country, have argued upon some of the principal points as 

 established facts ; essays have appeared in various parts of the Con- 

 tinent with a view to popularize more or less of the pi'inciples laid 

 down; and oven the constant repetition of vague party declama- 

 tions against the sj'stem are evidences of the ever firmer hold it is 

 taking upon the minds of the naturalists to whom, or at whom, these 

 denunciations aro addressed. The strongest opposition now kept 

 up amongst observing naturalists is, perhaps, that of the party in 

 France who still maintain the cause of spontaneous generation with 

 all the bitterness of a social dispute. Of a very difierent character 

 is Professor Agassiz's maintenance of the immutability of sjiecies; 

 for although, on starting for the Brazilian expedition above alluded 

 to, he avers that the conviction which drew him irresistibly into it 

 was that the combination of animals on that continent, where the 

 faunae are so characteristic and so distinct from aU others, would 

 give him the means of showing that the transmutation theory was 



