The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. 1855.07. As currents flow northwards in S. Hemisphere the most S. point T. del Fuego likely to be parent source of plants. CUL-DAR205.4.66-67. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 10. 2021. RN1

NOTE: The brown crayon number '20' indicates that this document was filed by Darwin in his portfolio for the subject of Island endemism: plants.

Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR205.4 contains notes on geographical distribution and species.

[66]

July 1855

As currents flow northwards in S. Hemisphere the most S. point T. del Fuego likely to be parent source of plants

Law, when in 2 now separated areas, some species are in common there will be representative species - N. America & Europe. New Zealand & Chile - Fuegia & Europe. This law is quite independent of means of communication. To make case strongest it shd be independent of any close resemblance in physical conditions.

[in margin:] (I doubt whether this is much good.

[67]

As India goes only above 10º N. & as temperate plants live in Ceylon & Neilgherries, it may be doubted whether any or few Tropical plants lived in India during cold period. (Ceylon has some extra Tropical plants). Africa wd perhaps (study isothermal) Keep most & fewer wd colonise India afterwards & have Africa & Madagascan character of Indian Flora - Malayan arch wd be more equable Tropical & Africa probably more extreme

[67v]

Tropical during cold period.—

I see is [Done] Isothermal at each 1/4 [months] N Africa is hottest place anywhere near. But I must look to Borneo for same object.

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