Summary

Birds has gone to the printer.

Continues "to collect all kinds of facts about ""varieties and species"" " for his "some-day work".

Would be grateful for descriptions of offspring of crossbred domestic animals.

Summary

In a revise [of Birds] CD has altered "Colaptes Chilensis Vigors" to "Chrysoptilus Chilensis G. R. Gray". Is that right?

Summary

Sends proof of index of final number of Birds for checking.

Summary

Answers a number of queries from Lyell concerning geography and geology of Chiloé Island and its relationship to the Cordilleras.

Asks about "perched rocks" on Jura and notes their relevance to Louis Agassiz’s theory. Discusses Agassiz’s view on Jura.

Mentions seeing Robert Brown.

Notes R. I. Murchison’s discovery of shells in central England.

Weakness of negative evidence.

Summary

Looks forward to the paper on CD’s edible fungus specimen from Tierra del Fuego [read 16 Mar 1841; Trans. Linn. Soc. Lond. 19 (1845): 37–43].

Sends a correction: Fagus betuloides, not F. antarctica, is the common tree of Tierra del Fuego.

Summary

Discusses the role of ice in determining the geological features of the Jura. Mentions view of Agassiz. Objects to idea of "a [sea of ice] carrying rocks". Notes Agassiz’s earlier view of "ice expanded in the line of the Great Swiss Valley". Comments on Pentlands.

Summary

Has enjoyed reading LA’s book [Études sur les glaciers (1840)].

Hopes LA will pardon manner in which CD has alluded to his work on glaciers in his Journal of researches, of which he sends a copy.

Summary

Defends his theory [in "Parallel roads of Glen Roy" (1839), Collected papers 1: 87–137] against the view that the "roads" were formed by glacial action.

Summary

Discusses at length Louis Agassiz’s book [Études sur les glaciers (1840)] and Agassiz’s explanation of moraines. Defends his own theory of the importance of floating ice. Relates glacier theory to his own interpretation of Glen Roy.

Mentions a paper he is writing on South American boulders and till [Collected papers 1: 145–63].

Summary

The Smith, Elder & Co. account for the now published fifth number of the third part of the Zoology is presented.

Summary

Sends paper on erratic boulders [Collected papers 1: 145–63] to the Society. Has taken two months to complete it because of illness.

Summary

The third number of part four of the Zoology has been published. CD transmits the Smith, Elder & Co. account.

Summary

Thanks recipient for finding reference on carbonate of lime. Doubtful when he will publish his geological memoranda.

Summary

Discusses various types of coral reefs on which he has been collecting notes. Views of C. G. Ehrenberg. His conception of the formation of Bermuda.

Pessimistic about the effect of his poor health on his scientific work.

Summary

Consents to be godfather to WDF’s child.

Sends family news.

Summary

Reports detailed observations on humble-bees boring holes in flowers to extract nectar instead of brushing over the stamens and pistils. Some hive-bees seem to use the holes made by the humble-bees; speculates that this would be a case of acquired knowledge in insects.

Summary

Sends elephant tooth from Africa. Suggests it may be interesting in light of his [mistaken] memory of Cuvier’s opinion about tusk brought from Peru by Humboldt.

Summary

Sends news of his house-hunting.

Envies WDF his discovery of Cheirotherium footprints.

Summary

Asks if JPG can supply him with the source of M. Cordier’s assertion that the reef of Vanikoro is of recent formation.

Summary

Tells WAL where specimen of Cynoglossum sylvaticum may be seen growing.