The Wallace-Darwin Correspondence 



No doubt, direct evidence of seeds being carried great 

 distances through the air is wanted, but, I am afraid, can 

 hardly be obtained. Yet I feel the greatest confidence that 

 they are so carried. Take for instance the two peculiar 

 orchids of the Azores (Habinaria species) : what other mode 

 of transit is conceivable ? The whole subject is one of great 

 difficulty, but I hope my chapter may call attention to a 

 hitherto neglected factor in the distribution of plants. 



Your references to the Mauritius literature are very in- 

 teresting, and will be useful to me ; and again thanking you 

 for your valuable remarks, believe me yours very faithfully, 



Alfred K. Wallace. 



Pen-y-hryn. St. Peter^s Road, Croydon. November 21, 1880. 



My dear Darwin, — Many thanks for your new book 

 containing your wonderful series of experiments and 

 observations on the movements of plants. I have read the 

 introduction and conclusion, which shows me the import- 

 ance of the research as indicating the common basis of 

 the infinitely varied habits and mode of growth of plants. 

 The whole subject becomes thus much simplified, though 

 the nature of the basic vitality which leads to such won- 

 derful results remains as mysterious as ever. — Yours very 

 faithfully, Alfred E. Wallace. 



Pen-y-hryn, St. Peter's Road, Croydon. January I, 1881. 



My dear Darwin, — I have been intending to write to you 

 for some weeks to call your attention to what seems to me 

 a striking confirmation (or at all events a support) of my 

 views of the land migration of plants from mountain to 

 mountain. In Nature of Dec. 9th, p. 126, Mr, Baker, of 

 Kew, describes a number of the alpine plants of Mada- 

 gascar as being identical species with some found on the 

 mountains of Abyssinia, the Cameroons, and other African 



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