18/6.] GEOGRAPHICAL DISTRIBUTION. 231 



mammals, but I must hope that you are right. I think you 

 will have to modify your belief about the difficulty of 

 dispersal of land molluscs ; I was interrupted when beginning 

 to experimentize on the just hatched young adhering to the 

 feet of ground-roosting birds. I differ on one other point, 

 viz. in the belief that there must have existed a Tertiary 

 Antarctic continent, from which various forms radiated to the 

 southern extremities of our present continents. But I could 

 go on scribbling for ever. You have written, as I believe, a 

 grand and memorable work which will last for years as the 

 foundation for all future treatises on Geographical Distribution, 

 My dear Wallace, yours very sincerely, 



CHARLES DARWIN. 



P.S. You have paid me the highest conceivable compliment, 

 by what you say of your work in relation to my chapters on 

 distribution in the ' Origin,' and I heartily thank you for it. 



[The following letters illustrate my father's power of taking 

 a vivid interest in work bearing on Evolution, but unconnected 

 with his own special researches at the time. The books 

 referred to in the first letter are Professor Weismann's 

 ' Studien zur Descendenzlehre,' * being part of the series of 

 essays by which the author has done such admirable service 

 to the cause of Evolution :] 



C. Darwin to Aug. Weismann. 



Jan. 12, 1877. 



... I read German so slowly, and have had lately to read 

 several other papers, so that I have as yet finished only half 

 of your first essay and two-thirds of your second.?' They 

 have excited my interest and admiration in 'tSe^' highest 

 degree, and whichever I think of last, seems to me the most 



* My father contributed a pre- lation of Prof. Weismann's 'Stii- 

 fatory note to Mr. Meldola's trans- dien,' 1 880-81. 



