Summary

Comments on cool-period MS. Still believes geographical changes principal cause of former changes of climate.

Summary

Admits that occasional transport is not a well-established hypothesis but believes it more probable than continental extension as an explanation for the stocking of islands.

Summary

"It [Rhamnus catharticus?] is certainly a case of dimorphic become dioecious."

Summary

Discusses pigeon and poultry woodcuts [for Variation].

WBT’s poultry book is at last in the hands of a solvent publisher [The poultry book (1867)].

Summary

His reasons for rejecting Atlantis hypothesis connecting Madeira and Canary Islands.

Summary

ARW’s simple explanation of dimorphic forms is satisfactory.

On "non-blending" of certain varieties, CD thinks ARW has not understood him. He does not refer to fertility. He crossed two differently coloured varieties of peas and "got both varieties perfect, but none intermediate". Something like this must occur in ARW’s butterflies.

Summary

Asks JL to look up a paper by Thomas Hincks on Polyzoa or Bryozoa [Q. J. Microsc. Sci. 2d ser. 1 (1861): 278–81].

Summary

Requests copy of paper read at Amsterdam Horticultural Congress, on graft-hybrids like that of Cytisus adami [see 5018].

Summary

More on continental extension vs transport [or migration] hypothesis. New questions raised. On Madeira, why were insects and plants changed so much, birds hardly at all?

Erratic boulders of the Azores.

Summary

Discussion of Mrs Agassiz’s letter [to Mary Lyell, forwarded to CD] regarding S. American glacial action,

with comments on Bunbury’s letter on temperate plants.

Refers to opinions of Agassiz, David Forbes, Hooker, and CD on glacial period and glaciers.

Wishes he had published a long chapter on glacial period [Natural selection, pp. 535–66] written ten years ago.

Tells of death of his sister, Catherine, and other family matters.

Summary

Had Busks and Lyells to dinner.

Examines and criticises evidence for CD’s hypothesis that the glacial period was not one of universal cold. Physicists deny its possibility.

Summary

Gives details of enclosed MS on cool period. Mentions Hooker’s opposed "axis of the earth" view. Causes of glacial period are beyond CD; "cannot believe change in land and water being more than a subsidiary agent".

Summary

Orders Richard Owen’s Anatomy of vertebrates [1866–8],

subscribes to Annals and Magazine of Natural History,

and orders three back numbers of Medical Times and Gazette.

Summary

Has read FM’s paper on sponges ["Über Darwinella aurea", Arch. Miskrosk. Anat. 1 (1865): 344–53] with interest.

Has also read FM’s work on the metamorphoses of Peneus [Ann. & Mag. Nat. Hist. 3d ser. 14 (1864): 104–15], an interesting and important embryological discovery.

CD regards Louis Agassiz’s opinions as valueless.

Summary

Memorial to the Chancellor of the Exchequer from the fellows of the Royal, Linnean, Geological, and Zoological Societies of London, stating the importance of separating the administration of the national natural history collections of the British Museum from that of the library and art collections, and placing it in the hands of one officer, immediately responsible to one of the Queen’s ministers.

Summary

Identifies a plant.

CD will not find Hermann Schacht’s Lehrbuch [der Anatomie und Physiologie der Gewächse (1856–9)] at the Linnean Society Library.

Summary

Thanks CL for Hooker’s letter.

Discussion of Hooker’s views on glacial action and temperature with specific reference to S. America.

His squabbles with Hooker on transport of seeds via water currents,

temperate plants, and preservation of tropical plants during cooler period.

Expresses interest in seeing Agassiz’s letter.

Summary

Sends copy of Land and Water, a journal he now edits. Has quit the Field. Asks CD to patronise his columns with queries, as other zoologists do.

Summary

Discusses exchange of photographs with German scientists.

Comments on attitudes of German scientists toward CD’s theory.

Names several scientists who exchanged photographs: Braun, Virchow, Leydig, and Dohrn.

Summary

Alterations to the woodcuts of poultry for Variation.