ON THE DIRECTIVITY OF LIFE. 



255 



Selection " and " Self-adaptation " are iriutuaUy exclusive. In 

 fact the former has really no facts whereon to base it, only 

 assumptions. 



In conclusion, how do we now stand with regard to Evolution 

 by the Directivity of Life ? 



1. Ear more offspring are born than can possibly live. 



The majority perish by fortuitous destruction. 



2. As long as there is no change in the environment, the 



species remains unchanged ; the slight individual 

 differences occurring in all organisms are of no 

 account, as a rule, in species-making. 



3. By emigration or transference to a different environ- 



ment, all the offspring of the same kind, if any change 

 is necessary, change accordingly ; the adaptations 

 appearing during growth to the adult stage. 



4. If such changed organisms live for a sufficient number 



of generations under the same conditions in which 

 their variations were evolved; then, if they be 

 restored to the old environment or to some other new 

 one, the variations may be hereditary and mostly are 

 permanent ; and Evolution will be thoroughly estab- 

 lished, without the aid of Natural Selection. 



Discussion. 



The Eev. A. Irving, D.Sc, B.A., proposed a hearty vote of thanks 

 to Professor Henslow for what might perhaps be considered, from 

 the scientific side, the most important paper read before the 

 Institute during this session. He thought it would be found to 

 answer the criticisms of those who had attacked his views as to 

 {a) the truth of Evolution as a theory (within its proper limits) ; 

 (h) the necessity of recognising directivity as a factor of Evolution 

 itself. The speaker quoted the words of Professor Henslow's paper 

 (p. 248) :— 



" I assume that every one present is a believer in Evolution, 

 though, like myself, he may not accept Darwinism, i.e., Darwin's 

 theory of the Origin of Species hy Natural Selection, to account for 

 Evolution." 



The author of the paper had confined himself to the strictly 

 scientific side of the question, and had thus placed the whole matter 



