Summary

Brian Hodgson reading CD’s Journal of researches with delight.

Forwarding breeding pamphlets.

JDH recommends P. S. Pallas on degeneration.

CD’s facts on sex in barnacles startling.

Hugh Falconer’s health.

Summary

Though correspondence has never ebbed so low, CD is constantly in his thoughts.

Observations on cheetahs used as domesticated hunting animals.

Finds geographical barriers sometimes separate species, but also finds species that remain separate where there are no barriers to migration.

Colour "individuates" isolated animal species.

Plains and alpine animal distribution show altitude not strictly analogous to latitude.

Impact of timber cutting on climate has led to extinction of crocodiles.

Will discuss coal formation in letter to Edward Forbes.

CD often asked whether isolated mountains in southern latitudes had closely allied representatives of Arctic and north temperate plants; JDH has found a representative barberry.

Making for Darjeeling via Calcutta.

Summary

Continues prior letter of this date. Has received CD’s [1202]. Thanks CD for saving his correspondence.

Sent "a yarn about species" in October mail.

Some "puerile" JDH letters printed in Athenæum.

Requests CD extract anything valuable from his letters to CD and Lyell for Athenæum.

CD’s complemental males in barnacles wonderful.

Warns CD to drop his battle about perpetuity of names in species descriptions.

Summary

Spoke too harshly about CD’s involvement in nomenclatural reform.

JDH used to think CD "too prone to theoretical considerations about species", hence was pleased CD took up a difficult group like barnacles. CD’s theories have progressed but JDH not converted. Sikkim has not cleared up his doubts about CD’s doctrines.

Argument with Falconer.

Summary

CD partly right. JDH was calling "stratification" what CD calls "foliation". Answers CD’s question on cleavage foliation in Himalayas. Glacial action.

Charmed by CD’s Admiralty instructions on geology [in Manual of scientific enquiry (1849), Collected papers 1: 227–50], but complains he does not give prices of books and instruments he recommends.

Summary

Pleasure at receiving CD’s scientific letters to JDH and Hodgson.

The H. Wedgwoods’ pecuniary loss.

Condolences at CD’s father’s death.

Rajah harasses JDH’s work. Lack of supplies, rain, malarial valleys, and landslips make going difficult. Cannot get into Tibet.

"Twenty species [of plants] here [Camp Sikkim] to one there [Tierra del Fuego?] always are asking me the vexed question, ""where do we come from?""."

From observation of terraces descending to steppes and plains of India, he thinks that the Himalayas were once a grand fiord coast.

Has information CD requested on Yangsma valley. JDH’s detailed hypothesis of origin of dam there. Does not agree with CD’s interpretation.

Summary

Falconer’s misbehaviour.

Geology of Khashia [Khasi] mountains. Speculations on mountain building and origin of Himalayas.

Summary

Physical description of Sikkim mountains.

Travelling through Kinchin snows.

Transported boulders.

Summary

Hugh Falconer’s misbehaviour.

Waiting out rains at Brian Hodgson’s.

Will make botanical transverse section of Himalayas from plains to snow.

Arrangements to pass Sikkim Rajah’s territory.

No evidence of glacial or diluvial action in sub-Himalayan mountains. No evidence of detrital coal formation.

Hodgson’s replies to CD on introduced species and hybrids.

Summary

Comments on paper by DM ["On the parallel roads of Lochaber", (1847) Trans. R. Soc. Edinburgh 16 (1849): 395–418]. "I am not in the least convinced about the Barriers … [but] I am very much staggered in favour of the ice-lake theory of Agassiz & [William] Buckland." Will "send a letter to the Scotsman, in which I give briefly my present impression".

Cites facts mentioned in South America possibly of use to DM.

Summary

Thanks Mrs Lyell for barnacle specimens.

Mentions Agassiz’s classification of saurians.

Discusses letter from Chambers on "roads" in Scottish glens; views of Agassiz and Buckland on the glens.

Is reading Hugh Miller [First impressions of England and its people (1847)].

Summary

Sends a letter for JW to forward to Charles Stokes concerning the purchase of Leeds and Bradford railway shares for Emma Darwin’s trust fund.

Summary

George Bentham’s list of aberrant plant genera. JDH appended the number of species in each genus according to E. G. Steudel’s catalogue [Nomenclator botanicus (1840–1)] and according to JDH and Bentham.

JDH speculates on effect of splitting Australia longitudinally on distribution; it becomes an argument for new creations.

Summary

CD makes progress with barnacles. Describes "supplemental" males in detail. In working out metamorphosis, their crustacean homologies followed automatically.

CD opposes appending first describer’s name to specific name.

Summary

If FJM wishes to sell the fossils he has discovered, CD suggests he appoint some agent to dispose of them.

Is surprised at the account of the earthquake in the pampas.

Offers to send his South America.

Greatly admires FJM’s zeal

and would welcome any information on the domestic animals of La Plata.

Summary

Will send village carrier for volumes [of the Trans. Agric. & Hortic. Soc. India].

Summary

Health bad, cannot get to Kew.

Will send Nulliporae to [L. A.?] Reeve.

Summary

Differences in variability of species within a single genus. Further observations on Lycopodium.

Interested in Humboldt’s river with different floras on opposite banks, and other unexplained cases of very local distributions.

Summary

Comments on letter by Bernhard Studer ["Remarks on the geological relations of the gneiss of the Alps", Edinburgh New Philos. J. 42 (1846–7): 186] and on article by DS ["On slaty cleavage", J. Geol. Soc. Lond. 3 (1847): 74–105]. Discusses geological cleavage and foliation.

Summary

Comments on David Milne’s paper ["On the parallel roads of Lochaber" (1847), Trans. R. Soc. Edinburgh 16 (1849): 395–418]. CD still believes in marine origin. Rejects barrier of detritus at mouth of Glen Roy. If roads were formed by lake, it must have been ice-lake.

Comments on evidence of glaciers and icebergs in North Wales. Thinks pass caused by tidal channel, not river. Suggests that RC make altitude measurements at various points.