142 THE WRITING OF THE 'ORIGIN OF SPECIES.' [1858. 



to nearly the same conclusion with you, though unable to 

 support the notion in any detail. Furthermore, by a curious 

 coincidence, expression has been for years a persistent subject 

 with me for loose speculation, and I must entirely agree with 

 you that all expression has some biological meaning. I hope 

 to profit by your criticism on style, and with very best thanks, 

 I beg leave to remain, dear Sir, 



Yours truly obliged, 



C. Darwin. 



C. Darwin to J. D. Hooker. 



Down, Dec. 24th [1858]. 



My DEAR HOOKER, Your news about your unsolicited 



salary and house is jolly, and creditable to the Government. 



My room (28 X 19), with divided room above, with all 



fixtures (and painted), not furniture, and plastered outside, 



cost about ,500. I am heartily glad of this news. 



Your facts about distribution are, indeed, very striking. 

 I remember well that none of your many wonderful facts 

 in your several works, perplexed me, for years, more than 

 the migration having been mainly from north to south, and not 

 in the reverse direction. I have now at last satisfied myself 

 (but that is very different from satisfying others) on this 

 head ; but it would take a little volume to fully explain 

 myself. I did not for long see the bearing of a conclusion 

 at which I had arrived, with respect to this subject. It is, 

 that species inhabiting a very large area, and therefore exist- 

 ing in large numbers, and which have been subjected to the 

 severest competition with many other forms, will have 

 arrived, through natural selection, at a higher stage of per- 

 fection than the inhabitants of a small area. Thus I ex- 

 plain the fact of so many anomalies, or what may be called 

 " living fossils," inhabiting now only fresh water, having been 

 beaten out, and exterminated in the sea, by more im- 



