RECORD: Darwin, C. R. 1855.03. Waterhouse says he used to think that probably all species of genus equally common somewhere. CUL-DAR205.3.173. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 1.2022. RN1
NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR205.3 contains notes on distribution of animals.
The brown crayon number '19' indicates that this document was filed by Darwin in his portfolio for the subject of Island endemism: animals.
Watson, Hewett Cottrell. 1847-59. Cybele Britannica; or British plants, and their geographical relations. 4 vols. London. [Darwin Library in CUL. Abstracts in CUL-DAR46.2.B48; CUL-DAR46.2.B49; CUL-DAR46.2.B53; CUL-DAR71.112-115; CUL-DAR205.10.75.]
[173]
March 1855
Waterhouse says he used to think that probably all species of genus equally common somewhere, but now he is sure that those species which are found in many different places are individually most numerous. ie this is law deduced from Watsons Cybele
(19)
Colymbetes &c of which close representative species are so widely distributed, have individually very wide ranges. But he remarks that those water insects which come to the surface, as Gyrinus differ far more in different countries. This looks strongly as if more equability of temperature was cause of similarity.
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 14 January, 2023