Summary

Sends a paper on reproductive modes of Leptodera ["Organisation und Fortpflanzen von Leptodera", Schr. Ges. Beförd. Naturw. Marburg (1869)].

Criticises Ernst Haeckel’s work as too unripe and enthusiastic.

Asks CD for some specimens of cirripedes in pupal stage for a work in progress.

Summary

Believes Portuguese habit of removing tails of pointers is responsible for birth of some tailless dogs.

Summary

On development of horns in fawns of fallow deer.

Summary

Thanks JP for his book Vesuvius [1869].

Summary

Thanks CC for two memoirs [see 6575. The other was possibly "Die Cypris-ähnliche Larve der Cirripedien", Schr. Ges. Beförd Naturw. Marburg (1869)].

Haeckel is too enthusiastic and too bold in drawing conclusions.

CD sees no reason to add to what he says on isolation, in new edition of Origin.

Lists specimens he has available for CC’s intended study of metamorphoses of Lepas.

Summary

Argues that [general variability] of species, not single variations or sports, is basis for modification and adaptation to new conditions.

Summary

DF’s opinion of Gustav Jenzsch’s book [Mikroskopische Flora und Fauna (1868)]. Encloses extract of a letter from Ferdinand Zirkel also mentioning Jenzsch’s work.

Summary

Returns book with thanks. "Joyfully accepts" idea of the warming of Southern Hemisphere during glacial period in the Northern. Lyell is unwilling.

Mentions H. N. Moseley’s study of descent of glaciers [Proc. R. Soc. Lond. 17 (1869): 202–8].

CD greatly troubled by problem of age of the earth and calculations of Sir William Thomson. Asks about changes in the form of the globe.

Summary

Requests authorisation to translate Journal of researches into French.

Summary

Statement of sum due from Rev. Robinson "On account of School".

Summary

Corrects T. M. Brewer’s statement, cited in the Origin, that the American cuckoo never uses other birds’ nests. [See Origin, 5th ed., p. 266.]

Summary

A case of fighting in crabs (Portunus puber against Carcinus maenas) [see Descent 1: 332].

Summary

CD expressed himself badly. F. Jenkin’s argument was against single variations ever being perpetuated.

Summary

Sends translation of Mr Steiger’s letter responding to question CD had asked about growth of horns of merino rams.

Summary

Discusses case of tailless dogs.

Does not intend to follow up work on variation under domestication.

Asks for specimen of Drosophyllum from Portugal.

Summary

Lyell says CD is revising what he says about the Weald in the Origin. Asks CD to look at his subaerial denudation views in his book [Physical geology and geography of Great Britain, 2d ed. (1864)].

Summary

Asks JM to grant permission for a French translation of his "Naturalist’s voyage" [Journal of researches].

Summary

Gives consent, which is unnecessary because term of protection has expired, for French translation of Journal of researches.

Is at a loss to know how many copies of F. Müller’s Facts and arguments for Darwin to print.

The printer is ready for copy for a new "edition" of Variation. [Presumably another issue. 2d edition did not appear until 1875.]

Summary

Received and read ACR’s Physical geology. Places him at head of the subaeria denudationists. Unfortunately CD confounded William Whitaker’s article with ACR’s views and gave Whitaker credit for first producing the evidence. Will rectify it now. Has eliminated the rubbish he wrote on the Weald and will add a paragraph on importance of subaerial denudation.

Summary

Argues for great age of earth before the Cambrian period. Opposes measuring age from secular cooling. Opposes Sir William Thomson. Lyell’s error on secular cooling.

Thanks for Moseley citation ["On the mechanical possibility of the descent of glaciers", Proc. R. Soc. Lond. 17 (1869): 202–8].

In Edinburgh he feels out of touch with latest developments.