From:
Francis Darwin
To:
Charles Robert Darwin
Date:
24 and 25 July 1878
Source of text:
DAR 162: 60, DAR 209.6: 198
Summary:
Notes Julius Sachs’s opinion on the heliotropism of moulds: he can see no use in the response.
C. E. Stahl is working on swarm spores which can be made both helio- and apheliotropic.
Sachs has told him that some ferns sleep, and he suspects that some grasses may move.
Sachs also feels they may be working at bloom from a wrong point of view and suggests leaves may need to keep dry in order to keep their stomata open.
Contributor:
Darwin Correspondence Project