Discusses books returned
and invites him to Down for a few days.
Showing 1–20 of 23 items
Discusses books returned
and invites him to Down for a few days.
Queries on ratios of species to genera on southern islands. CD’s observations on distribution of Galapagos organisms, and on S. American fossils, and facts he has gathered since, lead him to conclusion that species are not immutable; "it is like confessing a murder".
C. G. Ehrenberg would like some earth from Galapagos, Tierra del Fuego, and the Falklands; wishes to hunt for Infusoria.
Thanks for information for Ehrenberg.
Has just completed Volcanic islands.
Sends queries on Galapagos flora in particular and island floras in general; also on relationship of wide-ranging species to wide-ranging genera.
Affinity of Galapagos with nearest Pacific islands. Relationship between ranges of species in time and space. Comparison of Malden Island and Galapagos plants. Affinities of Oceania plants with continental floras.
Advice to JDH on problems of printing and publishing.
Remarks on differences of species between islets of Galapagos group.
Asks JDH to forward publishing information to J. E. Gray.
Has received JDH’s infusorial specimens for Ehrenberg.
Thanks for JDH’s interesting details about the Galapagos.
Clarification of CD’s query about the relationship between the range of a genus and the ranges of its constituent species.
Thanks for information on printing charges
and for clarifying "typical forms".
In a few days CD will go away for six weeks.
Asks if J. E. Gray has returned [printing] estimates for Zoology.
Henslow has some Galapagos plants which he forgot to forward to JDH.
Encloses letter from Ehrenberg [758] about Infusoria.
Intends to visit Kew.
Health and weather permitting, CD proposes to visit Kew.
Encloses letter from Ehrenberg [762], who wants information on deep-sea soundings from JDH’s voyage, and on isolated islands.
Encloses Ehrenberg letter, Galapagos seaweed, and specimens of Conferva.
H. Denny would like specimens of Antarctic Pediculi.
Encloses pamphlet from Ehrenberg who asks about deep-sea soundings from JDH’s voyage.
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".
Origin of Antarctic brash ice.
Further on case of Lycopodium: does JDH know any genera of plants whose species are variable in one continent but not in another? Discussion on variations between floras as regards species richness, and factors affecting geographical distribution. On species, CD expects "that I shall be able to show even to sound naturalists that there are two sides to the question of the immutability of species; – that facts can be viewed and grouped under the notion of allied species having descended from common stocks". Mentions books and papers for and against species mutability. CD believes past absurd ideas arose from no one’s having approached subject on side of variation under domestication.
Would like to see Clarke’s paper
and would welcome visit from JDH.
Would like JDH to visit. Regrets he will not be fit to visit JDH.
Instructions for JDH’s trip to Down.