To J. D. Hooker [April 1852]1
(1) Prevalence of genera2 varying in one quarter of world & not in another, as in Rubus in Europe & Himm:—or varying universally as in Senecio.
Does3 any individual species keep pretty constant in one quarter & vary in another quarter? or vary in one particular way in one region, & differently in another?
2. Do the local or widely distributed species vary most?4
3. When an organ or part varies to a quite remarkable degree in the different species of a genus, does it not vary in some degree within the limits of the same species?5 Thus the position of the radicle6 said to vary in Guttiferæ, hence I believe would vary slightly in some of the individual species. So position of the embryo in Helianthemum.7
(4) I shd be extremely glad to hear of any remarkable cases of variation in important organs within same species, in such rare cases as occurs.—8
(5) When an organ is developed in an extraordinaryly great degree it is (according to Waterhouse)9 apt to be variable in same species; so it is, when developed in an extraordinarily little degree (ie when rudimentary). Is this likewise case when organ developed in some very unusual manner?—10
(6) If a list of highly variable plants were made out, would they not usually be members of genera having many species?11
6. Cases of plants which must for ever self-fecundate themselves;12 do such occur? as in plants always fecundated in bud.—13
Footnotes
Bibliography
Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.
Hooker, Joseph Dalton. 1853–5. Flora Novæ-Zelandiæ. 2 vols. Pt 2 of The botany of the Antarctic voyage of HM discovery ships Erebus and Terror, in the years 1839–1843, under the command of Captain Sir James Clark Ross. London: Lovell Reeve.
Lindley, John. 1841. Elements of botany, structural, physiological, systematical, and medical; being a fourth edition of the Outline of the first principles of botany. London.
Lindley, John. 1853. The vegetable kingdom; or, the structure, classification, and uses of plants, illustrated upon the natural system. 3d edition with corrections and additional genera. London: Bradbury & Evans.
Miers, John. 1855. Observations on the structure of the seed and peculiar form of the embryo in the Clusiaceæ. Transactions of the Linnean Society of London 21: 243–58.
Natural selection: Charles Darwin’s Natural selection: being the second part of his big species book written from 1856 to 1858. Edited by R. C. Stauffer. Cambridge: Cambridge University Press. 1975.
Waterhouse, George Robert. 1846–8. A natural history of the Mammalia. 2 vols. London: H. Baillière.
Summary
Questions on variation in nature: taxa varying in one region but not another. Variation between vs within species. Rarity of variation in important organs within a species. G. R. Waterhouse’s views on variation in highly developed organs, which CD relates to variation in rudimentary organs.
Asks for cases of obligate self-fertilising plants.
[CD annotation proposes using the Steudel Nomenclator botanicus (1821–4) to determine if variable species occur in genera with many species.]
Letter details
- Letter no.
- DCP-LETT-1496
- From
- Charles Robert Darwin
- To
- Joseph Dalton Hooker
- Sent from
- unstated
- Source of text
- DAR 107: 66–7
- Physical description
- Amem 3pp & ADraft 4pp †, † (by CD)
Please cite as
Darwin Correspondence Project, “Letter no. 1496,” accessed on 2 December 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-1496.xml
Also published in The Correspondence of Charles Darwin, vol. 5