From:
Asa Gray
To:
Charles Robert Darwin
Date:
7 July 1857
Source of text:
DAR 205.9: 381; DAR 165: 98
Summary:
Believes, with CD, that extinction may be an important factor in explaining plant distributions, but sees no reason why the several species of a genus must ever have had a common or continuous area. "Convince me of that, or show me any good grounds for it … and I think you would carry me a good way with you". It is just such people as AG that CD has to satisfy and convince.
Feels that the crossing of individuals is important in repressing variation and perhaps in perpetuating the species, but instances some plants in which it cannot, apparently, take place.
Contributor:
Darwin Correspondence Project
