The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. 1874.12.05. Variability — Polymorphic species. CUL-DAR47.26. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 7.2022. 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-DAR47 contains notes for Natural selection chap. 7 'Laws of Variation'.

[26]

Dec 5/74/

Variability — Polymorphic Species

I can well believe that when sterility did not incidentally supervene between 2 incipient species they wd not be developed, & so far selection wd come into play & they would inter cross & make confusion more confounded— as in Hieracium & Rubu &c—

So these random vars being of no use another cause may have led to polymorphic species

The want of sterility wd be apt to arise probably no forms generated in same area & exposed to same conditions

Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)