Darwin on humus and the earthworm
Subtitle: the formation of vegetable mould through the action of worms with observations on their habits
By: Charles Darwin.  With an introduction by Albert Howard.
Contributors: Darwin, Charles, 1809-1882.
Publisher: Faber and Faber
Published: 1966
Place of publication: London
Number of pages: 153
Subjects: Earthwork; Humus; Soil fertility
Notes: First published in 1881 under title : The formation of vegetable mould through the action of worms.