Summary

Information concerning improvements in the Reader under new sponsorship.

Current reading and work [on pigeons for Ibis 1 (1865): 365–400, and catalogue of his collection of birds].

Book of travels postponed indefinitely.

Summary

Thanks CD for paper ["Climbing plants"].

Reports case of variation becoming at once hereditary – a crested blackbird with crested young.

Summary

Sends papers with comments. Convinced that the Aru pig is a species peculiar to New Guinea fauna, not a domestic animal that ran wild.

Admires CD’s paper ["Three forms of Lythrum", Collected papers 2: 106–31].

Summary

His distress that his engagement has been broken off.

Sends copies of two papers ["On the parrots of the Malayan region", Proc. Zool. Soc. Lond. (1864): 279–97;

"On the physical geography of the Malay Archipelago", J. R. Geogr. Soc. 33 (1863): 217–34].

Summary

Describes his view on colour [of plumage] of males and females – i.e., that absence of brilliant colour in either sex is due to need for protection in incubation, rather than to sexual selection.

Summary

Inquires about arrangements for the German translation and publication of their original Linnean Society papers [Collected papers 2: 3–19].

ARW thinks he has hit upon a solution to problem of geological time.

Summary

Discussion of his possible assistance on editorial work for revised edition of Descent.

Summary

Protective role of colours in caterpillars and butterflies. Sexual differences in colours of butterflies.

Summary

Comments on Fritz Müller’s book [Facts and arguments for Darwin].

Responds to CD’s corrections of his work [Malay Archipelago].

Plumage of birds of paradise.

Summary

Thanks for Variation.

Reports work on his travel book [The Malay Archipelago (1869)].

Summary

If CD is not convinced by his notes on sterility, ARW has little doubt that he is wrong. In fact he was only half-convinced by his own arguments.

Modifies his first proposition [a species varies occasionally in two directions, but owing to free inter-crossing the variations never increase] and further discusses the subject.

Encloses Berthold Seemann’s notes on flora of the Hawaiian Islands. Presence of European alpine species in Hawaiian volcanoes is a "hard nut" for geographical distribution [but see ARW’s Island life (1880), p. 323].

Summary

Dedication of Malay Archipelago to CD.

Comments on scientific papers.

Summary

Looks forward to reading Variation.

Explains how two or more female forms occur in one species through selection. The physiological problem remains of how each produces offspring like the other without intermediates. Is not CD’s case of varieties that will not blend the physiological test of a species needed for "complete proof of the origin of species"?

"Travels" postponed.

Summary

Thanks CD for 4th ed. of Origin.

Discusses abnormal sexual characters produced by mimicry. ARW’s papers on the subject.

Agassiz’s "marvellous" Amazonian glacier theory.

Summary

ARW responds to CD’s list of queries about expression. Suggests acquiring informants through publishing the queries in newspapers. His doubts about their importance.

Has submitted caterpillar question to Entomological Society.

Summary

On the Borneo cave exploration.

ARW will send his contribution to theory of origin of man. The vast mental and cranial differences between man and apes, whereas structural differences in other parts of body are small. The problem of explaining diversity of human races along with the stability of man’s form during all historical epochs. Discussion with "Anthropologicals" [following reading of ARW’s paper, "The origin of human races", before the Anthropological Society, 1 Mar 1864].

Summary

Offers enclosure demonstrating that natural selection could produce sterility of hybrids.

More on Pangenesis and the inadequacy of H. Spencer’s approach.