18701882] LYELL 337 



higher grade of organisation being evolved out of lower ones. Letter 250 

 Is not a very clever man a grade above a very dull one ? and 

 would not the accumulation of a large number of slight 

 differences of this kind lead to a great difference in the grade 

 of organisation ? And I suppose that you will admit that the 

 difference in the brain of a clever and dull man is not much 

 more wonderful than the difference in the length of the nose 

 of any two men. Of course, there remains the impossibility 

 of explaining at present why one man has a longer nose than 

 another. But it is foolish of me to trouble you with these 

 remarks, which have probably often passed through your 

 mind. The end of this chapter (XLIII.) strikes me as 

 admirably and grandly written. I wish you joy at having 

 completed your gigantic undertaking, and remain, my dear 



Lyell, 



Your ever faithful and now very old pupil, 



CHARLES DARWIN. 

 To J. Traherne Moggridge. Letter 251 



Sevenoaks, Oct. gth [1872]. 



I have just received your note, forwarded to me from my 

 home. I thank you very truly for your intended present, and 

 I am sure that your book ! will interest me greatly. I am 

 delighted that you have taken up the very difficult and most 

 interesting subject of the habits of insects, on which English- 

 men have done so little. How incomparably more valuable 

 are such researches than the mere description of a thousand 



in reality," he writes, " it cannot be said that we obtain any insight into 

 the nature of the forces by which a higher grade of organisation or instinct 

 is evolved out of a lower one by becoming acquainted with a series of 

 gradational forms or states, each having a very close affinity with the 

 other." ..." It is when there is a change from an inferior being to one 

 of superior grade, from a humbler organism to one endowed with new and 

 more exalted attributes, that we are made to feel that, to explain the 

 difficulty, we must obtain some knowledge of those laws of variation of 

 which Mr. Darwin grants that we are at present profoundly ignorant " 

 (op. cit., pp. 496-97). 



1 J. Traherne Moggridge (1842-74) is described by a writer in Nature 

 Vol. XL, 1874, p. 114, as "one of our most promising young naturalists." 

 He published a work on Harvesting Ants and Trap -door Spiders, 

 London, 1873, and wrote on the Flora of Mentone and on other subjects. 

 (See The Descent of Man Vol. I., Ed. n., p. 104, 1888.) 



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