362 THE president's address. 



we are acquainted here. On the other hand, it follows from the- 

 theory of panspermia that all forms of life throughout the 

 universe are related, and it is the opinion of Arrhenius that 

 the activities of life are connected inseparably with the protein - 

 compounds. 



Let us now try to imagine what was the fate of the earliest 

 germs of life that, on the theory of panspermia, colonised our 

 globe when it was first in a condition to support life. In the 

 first place it may be noted that the filter-passers of our day show- 

 by their activities distinct specific differences amongst themselves. 

 It is therefore possible that more than one variety of living^ 

 particle came to our planet, and that there may have been some 

 selection amongst those that came. 



The first need of the tiny germ, when the warmth of our earth 

 awoke its long-dormant activities, would be food. It is possible 

 that some of these heavenly visitors may have acquired already, 

 in another world, the power of constructing organic matter from 

 inorganic ; but it is more probable that a supply of organic matter 

 was a necessity for them, since all the filter-passers and Chlamy- 

 dozoa known to us at present are parasites. We may suppose, 

 therefore, with Sir Ray Lankester, that a certain epoch of the 

 earth's history was favourable to the synthesis of organic matter 

 of at least a certain degree of complexity ; and that thus a supply 

 of food was provided upon which the Arrhenian germs were able 

 to make a start. In any case they must have multiplied rapidly, 

 adapted themselves to various modes of life, and given rise by 

 natural evolution to the various forms of life on our globe through 

 an immense period of time. Arrhenius considers that the interval 

 of time between the first appearance of life on the globe and the 

 Cambrian epoch was at least as great as that from the Cambrian 

 epoch to the present day. 



In the preceding paragraphs I have tried to set forth critically 

 the two opposed theories of the origin of life, one or the other of 

 which must be true so far as its main thesis is concerned ; that 

 is to say, life must either have originated on the earth or have 

 come to it from without. He who would attempt, however, to 

 judge and decide between these two possibilities would be indeed 

 a bold and a rash man. Scientific knowledge of living things is 

 at present much too incomplete in at least two directions to 

 render any such judgment even approximately just. We require 



