ORIGIN OF LIFE 179 



get far enough for that at the time when I was thinking 

 whether I could bring the subject into a lecture. What 

 then occurred to me was little more than this : — 



Life on the earth most likely had its origin at one of 

 the poles, since there conditions that admit of its existence 

 would first occur as the planet was slowly cooling down. 



Gradually Life, now differentiated into Plant Life and 

 Animal Life, made its way towards the Equator, and in 

 so doing became more and more differentiated. 



Then must (?) have come a change which wholly or 

 almost wholly divested the poles or pole of Life, confining 

 it to equatorial regions. Such a change as this was 

 probably more than once repeated in the course of various 

 geological epochs. When things pretty much as we know 

 them now came to be established there was (and is) 

 probably very little if anything left of the primeval polar 

 life ; for setting aside the possible total extinction of it 

 through severity of climatic conditions, evolution would 

 have so far improved the forms that were travelling 

 polewards that any vestiges of the original polar life 

 would be swept away by the better-fitted newcomers. 



But of course all this, or very nearly all, is absolute 

 speculation. The most that can be said in its favour is 

 that such facts as we know do not seem to contradict it. 

 So long as the " Geological Record " is so imperfect I do 

 not see how we are to advance further. 



Moreover, you will see that my speculations had 

 reference to periods long anterior to even the Eocene. 

 In the Eocene period nearly all the big divisions that we 

 have now were already well established ; e.g. Birds, 

 Hesperornis and Ichthyornis, one Ratite the other Cari- 

 nate. If the Miocene coal-beds at Discovery Bay ever 

 yield any Vertebrate remains they will probably be 

 found very like things that now exist, and to judge from 

 the analogy of botanical remains, they may be more 

 like things of Europe and North America than those of 

 South America or New Australia, not to say New 

 Zealand.* 



* Letter to Col. H. W. Feilden, January 7, 1886, 



