From:
Hubert Airy
To:
Charles Robert Darwin
Date:
[before 15] July 1872
Source of text:
DAR 159: 16
Summary:
Outlines his theory on the origin of existing orders of leaf arrangement. Believes spiral and whorled orders have evolved from a primitive distichous arrangement. These arrangements permit a compact bud form of small surface area that can withstand external changes in temperature, and in particular can tolerate frost.
Contributor:
Darwin Correspondence Project
