164 EVOLUTION [CHAP. Ill 



Letter iro Page 5 of your letter : I agree to every word about the 

 antiquity of the world, and never saw the case put by any one 

 more strongly or more ably. It makes, however, no more 

 impression on me as an objection than does the astronomer 

 when he puts on a few hundred million miles to the distance 

 of the fixed stars. To compare very small things wilh great, 

 Lingula, etc., remaining nearly unaltered from the Silurian 

 epoch to the present day, is like the dovecote pigeons still 

 being identical with wild Rock-pigeons, whereas its " fancy " 

 offspring have been immensely modified, and are still being 

 modified, by means of artificial selection. 



You put the difficulty of the first modification of the first 

 protozoon admirably. I assure you that immediately after 

 the first edition was published this occurred to me, and I 

 thought of inserting it in the second edition. I did not, 

 because we know not in the least what the first germ of life 

 was, nor have we any fact at all to guide us in our specula- 

 tions on the kind of change which its offspring underwent. 

 I dissent quite from what you say of the myriads of years it 

 would take to people the world with such imagined protozoon. 

 In how very short a time Ehrenberg calculated that a single 

 infusorium might make a cube of rock ! A single cube on 

 geometrical progression would make the solid globe in (I 

 suppose) under a century. From what little I know, I cannot 

 help thinking that you underrate the effects of the physical 

 conditions of life on these low organisms. But I fully admit 

 than I can give no sort of answer to your objections ; yet 

 I must add that it would be marvellous if any man ever 

 could, assuming for the moment that my theory is true. You 

 beg the question, I think, in saying that Protococcus would be 

 doomed to eternal similarity. Nor can you know that the 

 first germ resembled a Protococcus or any other now living 

 form. 



Page 12 of your letter: There is nothing in my theory 

 necessitating in each case progression of organisation, though 

 Natural Selection tends in this line, and has generally thus 

 acted. An animal, if it become fitted by selection to live the 

 life, for instance, of a parasite, will generally become degraded. 

 I have much regretted that I did not make this part of the 

 subject clearer. I left out this and many other subjects, 

 which I now see ought to have been introduced. I have 



