Summary

About the researches of Ehrenberg. "I have … sent him several packets of objects from my voyage & that of Dr. Hooker".

Summary

Thanks for earth samples. Discusses Infusoria in samples from Galapagos and Cape Verde Islands. Would like samples from other sites. Will send further results of investigations.

Summary

Encloses letter from Ehrenberg [758] about Infusoria.

Intends to visit Kew.

Summary

Astonished that dust sample contains Infusoria. Thinks dust is volcanic. Will write account of falling dust [see 775]. Offers further samples.

Summary

Thanks for shipments of earth samples. Sends copy of article describing Infusoria in samples ["Einige vorläufige Resultate … über das Verhalten des kleinsten Lebens in den Oceanen", Ber. k. Preuss. Akad. Wiss. Berlin (1844): 182–207]. Asks for more information and samples, especially from the soundings of Ross’s expedition.

Summary

Health and weather permitting, CD proposes to visit Kew.

Summary

Sends four packets of lice and suggests writing to Dr A. Smith, "the S. African traveller", for assistance.

Summary

Encloses letter from Ehrenberg [762], who wants information on deep-sea soundings from JDH’s voyage, and on isolated islands.

Summary

Sends a specimen of rusty wheat from the banks of the Plata.

Asks for bits of peat he collected

and a bit of the paint used by Fuegians to colour themselves.

He will send these to C. G. Ehrenberg for analysis.

Summary

Urgently needs a Spanish map of the Cordilleras of central Chile near St Jago [Santiago].

Summary

Acknowledges receipt of the order for £48 4s. 8d., and offers full indemnity for the £5,000 deposited without security.

Summary

Encloses Ehrenberg letter, Galapagos seaweed, and specimens of Conferva.

H. Denny would like specimens of Antarctic Pediculi.

Summary

Declines to undertake to have AM’s journal published but recommends possible publishers in England.

Expresses scepticism about AM’s glacier theory. Emphasises role of floating ice instead. Mentions article by William Hopkins on movement of glaciers.

Summary

Can hardly believe he made a mistake in specimens sent to HD. Recopies numbers in case he transposed them. [Has to do with lice taken from a specimen of aperea and put into spirits during Beagle voyage.]

Summary

Thanks Horner for his letter [about Volcanic islands].

Discusses craters of elevation with respect to the views of Leopold von Buch and Élie de Beaumont. Compares Lyell’s views to those of continental geologists. Mentions reading A. D. d’Orbigny [Voyage dans l’Amérique méridionale (1835–47)].

Encloses note from Emma to Mrs Horner, inviting the Horners to visit Down.

Summary

Encloses pamphlet from Ehrenberg who asks about deep-sea soundings from JDH’s voyage.

Summary

Asks about CL’s new book [Travels in North America (1845)].

Discusses views of A. D. d’Orbigny on elevation.

Mentions reading W. H. Prescott [History of the conquest of Mexico (1843)].

Summary

Suggests there is a direct relation between temperature and abundance of plant species.

Summary

Has at last received first letter CGE wrote.

More specimens being sent.

Sends his sketch of paper ["Fine dust in the Atlantic Ocean" (1846), Collected papers 1: 199–203].

D’Orbigny considers Pampas clay deposit result of debacle. CD cannot doubt it is slow, estuary deposit. Would be grateful for information on this point.

Summary

Acknowledges note and parcel for Ehrenberg.

Considers why different areas have different numbers of species. Gives an example opposing JDH’s view that paucity of species results from vicissitudes of climate. CD has concluded that species are most numerous in areas that have most often been divided, isolated from, and then reunited with, other areas. Cannot give detailed reasons but believes that "isolation is the chief concomitant or cause of the appearance of new forms".