358 THE president's address. 



One method, however, judging by its results, seems to have been 

 much more successful, to have paid better, so to speak, than any 

 other the method, namely, whereby the living substance pro- 

 duced a pigment or class of pigments, sometimes yellow, red, or 

 brown, but most usually green, termed chlorophyll, by means of 

 which it is able to utilise the sun's energy in order to decompose 

 carbon dioxide, and to build up the carbon, together with 

 elements derived from water and inorganic salts in solution, to 

 form the living substance. The organisms which invented, so to 

 speak, this mode of life, flourished exceedingly, and gave rise in 

 process of time and evolution to the entire vegetable kingdom, 

 thereby permitting the evolution of the animal kingdom, 

 depending directly or indirectly for its sustenance upon plants. 



If any organisms exist at the present day which represent the 

 original type of living being in its primitive form, unchanged 

 through the ages, it is scarcely possible that they could still exist 

 free in Nature, since they would require an abundant supply of 

 organic nutriment, more abundant, probably, than would be 

 found occurring in Nature. It is probable, therefore, that such 

 organisms would have to be sought among parasitic or sapro- 

 phytic organisms; that is to say, obtaining their supply of organic 

 matter either fi-om a living body or from one that has lost its life 

 recently. 



In contrast with the view that life originated on the earth 

 itself, the suggestion has often been made that the first living 

 things, or the germs of life in some form, were brought by some 

 means to our earth from without. I will not attempt to review 

 or discuss the many theories of this kind that have been pro- 

 pounded ; I will confine myself to giving an account of the latest 

 in the field that, namely, of the famous chemist. Professor Svante 

 Arrhenius,* who has put forward a hypothesis based on grand 

 and wonderful conceptions. His theory starts with the notion 

 that the beginning of life is coeval with that of our universe ; 

 that is to say, that " life must always have been in existence, 

 however far back we may carry our thoughts," and that " life 

 itself is eternal, like matter and like energy," so far as our minds 

 can form a conception of eternity. With regard to this assump- 

 tion, however, it must be pointed out that matter and energy 



* Worlds in the Makiufj and The Life of the Universe. (Harper & 

 Brothers, London and New York.) 



