Note 22 — Chapter II · GENERAL CONSIDERATIONS ON THE MOVEMENTS AND GROWTH OF SEEDLING PLANTS.
Reading edition
The cotyledons, though bright green, resemble to a certain extent hypogean ones; see the interesting discussion by Haberlandt (‘Die Schutzeinrichtungen,’ etc., 1877, p. 95), on the gradations in the Leguminosae between subaërial and subterranean cotyledons.