Notes by HCW on the Origin dealing especially with divergence and convergence. Believes there is some natural tendency to converge into groups in opposition to divergence generated by natural selection.
Showing 1–11 of 11 items
Notes by HCW on the Origin dealing especially with divergence and convergence. Believes there is some natural tendency to converge into groups in opposition to divergence generated by natural selection.
Discusses the possibility of "convergence" occurring; believes it could be only very limited.
Returns reviews of Origin.
F. J. Pictet [Arch. Sci. Phys. & Nat. n.s. 7 (1860): 231–55] goes further than he himself realises.
Naturalists will resist CD’s views until faith in certain "impassable" barriers between existent species is shaken.
Gives CD an instance of convergence.
Difficulty of distinguishing varieties and species. Did HCW suggest a printed list that might help?
Polymorphic genera.
Distribution of varieties and subspecies.
George Maw’s review of the Origin [Zoologist 19 (1861): 7577–611].
Gives CD an instance of facts that can be read either way as to whether a plant (Veronica humifusa) is a species or a variety.
The Primula experiments of J. Sidebotham; HCW’s distrust of the results [see J. Sidebotham, "Specific identity of the cowslip and the primrose", Phytologist 3 (1849): 703–5].
Asks HCW’s help with his experiments on Lythrum salicaria, for which he needs flowers of the rare Lythrum hyssopifolia.
Cover containing some seeds mentioned in the letter to H. C. Watson, 28 May [1864], f.2 (S 4512).
Taeas [?] allied to L. hyssopifolia. [Cover containing packets of seed specimens.] Mentioned in the letter to H. C. Watson, 28 May [1864], f.2 (fS 4512).
Thanks HCW for Lythrum specimens.
CD has at last finished his Lythrum paper. ["Three forms of Lythrum", Collected papers 2: 106–31.]