ON BIOLOGY. 93 



matter, an hypothesis it may be said in passing quite 

 in harmony with the doctrine of evolution. Science, as 

 yet, is not in possession of any direct evidence which 

 could be considered demonstrative of the fact that any 

 such a phenomenon has ever taken place in Nature at 

 any time within the period of the recorded existence of 

 life upon the earth. You will remember that I said such 

 a theory is spoken of as the theory of abiogenesis. and 

 although we have no trustworthy proof of its actual 

 occurrence, "it need hardly be pointed out," as Huxley 

 says, that that "fact does not in the slightest degree 

 interfere with any conclusion that may be arrived at 

 deductively from other considerations that, at some other 

 time or other, abiogenesis must have taken place." From 

 these premises we are compelled to believe that the 

 progress for aetiology in the future must be the accumu- 

 lation of evidence in support of those other considera- 

 tions to which allusion has just been made, and that 

 such evidence will in time be forthcoming I make no 

 manner of doubt, any more than I entertain any doubt in 

 my mind that the deduction which can be made from it 

 will be so weighty that it will place the question of 

 abiogenesis upon as secure a foundation, in so far as its 

 occurrence is concerned, as that of any other inductive 

 hypothesis which has been accepted as good as proven by 

 all thinking people who ever pay any attention to such 

 matters. 



My remarks upon this subject would not be complete 

 did I not at least make brief allusion to the provisional 

 hypothesis, advanced by Darwin, which he termed "pan- 

 genesis," whereby he attempted to explain the phenom- 

 ena of reproduction in organisms. In one of his works he 

 says: 



'I venture to advance the hypothesis of pangenesis, 

 which implies that every separate part of the whole or- 

 ganization reproduces itself. So that ovules, spermato- 

 zoa, and pollen-grains the fertilized egg or seed, as well 

 as buds include and consist of a multitude of germs 

 thrown off from each separate part or unit," 



For some reason or other this hypothesis does not seem 

 to have excited any lasting interest, either in the lay or 

 scientific mind, although we cannot claim that as any 

 valid proof militating against its truth, and that is a 

 matter which time and amplification of our knowledge 

 in the premises alone can settle. 



Even the biogenetic view of the origination of life has 

 its enigmas for us to solve, and so far as the initial ques- 



