A detailed bibliography of this is given by Richard Curie A bibliographical history of the Ray Society, 1954. There is no indication that the two volumes are parts of the same work. Robert Hardwicke was publisher to the Society, and advertisements for this work, in later Darwins, often give his name alone as publisher. Curie states that the number of copies printed may not have been more than 800, that is about fifty more than the number of members of the Society at the time. He does not give the original price, but the English catalogue gives £2.2s. for the set. It appeared in facsimile in 1965, and it is also available on microfiches from the International Documentation Centre. Darwin spent much of his time for eight years, beginning in 1846, on this work and on the corresponding volume of the British fossil forms. They are his only contributions to formal taxonomy and are still held in high regard.
See also Darwin's Study of the Cirripedia by Marsha Richmond and W. A. Newman, Dates of publication of two of Darwin’s volumes on the Cirripedia (barnacles).
Darwin, C. R. 1851 [=1852]. Living Cirripedia, A monograph on the sub-class Cirripedia, with figures of all the species. The Lepadidæ; or, pedunculated cirripedes. London: The Ray Society. Volume 1 Text Image Text & image F339.1
NOTE: With thanks to The Charles Darwin Trust and Dr Mary Whitear for use of the Bibliographical Handlist. Copyright. All rights reserved. For private academic use only. Not for republication or reproduction in whole or in part without the prior written consent of The Charles Darwin Trust, 14 Canonbury Park South London N1 2JJ.
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