JDH not happy with CD’s explanation of the absence of north temperate forms in the Southern Hemisphere, given his explanation for the spread of sub-arctic forms to the south. [CD’s note is in response to JDH’s criticism.]
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The Charles Darwin Collection
The Darwin Correspondence Project is publishing letters written by and to the naturalist Charles Darwin (1809–1882). Complete transcripts of letters are being made available through the Project’s website (www.darwinproject.ac.uk) after publication in the ongoing print edition of The Correspondence of Charles Darwin (Cambridge University Press 1985–). Metadata and summaries of all known letters (c. 15,000) appear in Ɛpsilon, and the full texts of available letters can also be searched, with links to the full texts.
JDH not happy with CD’s explanation of the absence of north temperate forms in the Southern Hemisphere, given his explanation for the spread of sub-arctic forms to the south. [CD’s note is in response to JDH’s criticism.]
CD has suggested an explanation of how pike were introduced to a remote lake in Ireland by cormorants [carrying pike spawn on their feet or in their gullets].
Gives instances of sexual differences in the number of tarsi within species of Coleoptera and also variation in the number of tarsi between related species.
JDH’s contempt for R. I. Murchison.
There is a Cyperus species and a Pteris species endemic to hot volcanoes of Ischia. Why are there no other migrators?
Discusses the similarity in size, shape, and structure of the blood corpuscles of the Aves. Notes differences between the corpuscles of the domestic dog and some wild species.
Responds to CD’s letter. The ova of Salmonidae exposed to air, if kept moist, will stay alive up to 72 hours.
Comments on possibility of transport of seeds of Arctic plants by ice.
CD’s tabulation of colonists curious but explicable.
Working on Tasmanian flora; contemplating general essay on Australian distribution: Tasmania and Australia same alpine species; Swan River flora very peculiar and quite distinct from New South Wales.
Trying to establish new journal at Linnean.
Hybrid insects.
Description of the Salvages.
Variability of "transition groups" of insects; relation of variability to ranges of insects. The variability of wings, even within species. Reduction of flying ability on isolated islands.
Forbes’s "Atlantis" theory and insect fauna of the Atlantic islands, considered with regard to insect migrations.
Comparison of skulls of Ichthyosaurus and Cetacea.
JDH criticises C. J. F. Bunbury’s paper on Madeira [J. Linn. Soc. Lond. (Bot.) 1 (1857): 1–35].
Absence of Ophrys on Madeira suggests to JDH a sequence in creation of groups.
Why are flightless insects common in desert?
Australian endemism.
Is trying to procure some cocks for CD.
Believes Scotch deerhounds are mongrels.
Responds to CD’s questions about mountain vegetation of the Cape of Good Hope. The distribution of some plants provides problems for both migration and special creation hypotheses.
Has filled up CD’s paper [see 1674].
Distribution and relationships of alpine flora in U. S.
Notes on the interbreeding of different races of silkworm. [Forwarded with explanatory note by Edward Blyth.]
Finds Forbes’s continental theories, migration, and double creation are all unsatisfactory explanations of geographical distribution of plants.
Is currently working on problems of sea transport of plant species.
European plants on Australian Alps only explicable by double creations.
Discusses hybrid plants he has raised, particularly hybrids between Geum urbanum and G. rivale, which are very fertile and exhibit great variability. [See Natural selection, p. 102.]
Red and white campions: JSH regards them as races, not species; a flesh-coloured intermediate exists.
Sends a list of "close" species from his Manual of botany.
Hopes Hooker or CD will write an essay on species. Discusses some of the difficulties of defining botanical species.
Answers queries on Azores fauna and flora.