Has filled up CD’s paper [see 1674].
Distribution and relationships of alpine flora in U. S.
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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.
Has filled up CD’s paper [see 1674].
Distribution and relationships of alpine flora in U. S.
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.
Believes intermediate varieties are generally less numerous in individuals than the two states that they connect.
Discusses the difficulties of deciding what is the typical form of a species
and gives some opinions on the variability of introduced species compared with indigenous species.
Plants that are social in the U. S. but are not so in the Old World.
Distribution of U. S. species common to Europe.
Gives Theodor Engelmann’s opinion on the relative variability of indigenous and introduced plants and notes the effects of man’s settlement on the numbers and distribution of indigenous plants.
Outlines the ranges of northern U. S. species common to Europe. Hopes to investigate the resemblances between the floras of the north-eastern U. S. and western Europe. Discusses routes by which alpine plants appear to have reached U. S.
Discusses the ranges of alpine species in U. S. and considers the possible migration routes of such species from Europe.
Lists those U. S. genera which he considers protean and describes the U. S. character of some genera which are protean in Europe.
Describes how he distinguishes introduced and aboriginal stocks of the same species.
Discusses difficulties involved in deciding which genera are protean in the light of some comments by H. C. Watson.
Comments on species with disjoined ranges; does not feel, despite CD’s expectations, that they tend to belong to small families.
Gives the proportion of U. S. trees in which the sexes are separate [see Natural selection, p. 62].
Believes, with CD, that extinction may be an important factor in explaining plant distributions, but sees no reason why the several species of a genus must ever have had a common or continuous area. "Convince me of that, or show me any good grounds for it … and I think you would carry me a good way with you". It is just such people as AG that CD has to satisfy and convince.
Feels that the crossing of individuals is important in repressing variation and perhaps in perpetuating the species, but instances some plants in which it cannot, apparently, take place.
States he has "misgivings about the definiteness of species". Believes there is some inherent tendency for plants to originate varieties. Cross-fertilisation is likely in most cases but sees difficulties with plants like Adlumia.
List of close species taken from AG’s Manual of botany [1848].
Self-fertilisation in Fumariaceae.
[CD note on bees’ visiting some members of Fumariaceae.]
Agassiz denounces Origin as "atheistical";
AG is currently reviewing it [in Am. J. Sci. 2d ser. 29 (1860): 153–84].
Jeffries Wyman praises it, though not a convert.
American edition of Origin. AG’s assessment of the book’s weak and strong points. Suggests Jeffries Wyman would be a useful source of facts and hints for CD.
Arrangements for the American edition of Origin.
Cases of "dioecio-dimorphism" as in primroses are widespread. AG always considered them the first step toward bisexuality.
Gives some observations on the sensitivity of Drosera species and comments on cases of "dioecio-dimorphism".
Notes several cases of "dioecio-dimorphism" in different genera; feels the discovery of pollen that will act only on the pistil of another flower is most important. Believes CD should next turn his attention to investigating cases of "precocious fertilisation".
Discusses observations of his own and of John Torrey on dimorphism, especially in Amsinckia.
Is trying to find specimens of Houstonia for CD.
Discusses dimorphism and suggests CD investigate Valeriana.
Praises CD’s views with respect to the U. S. Civil War and relations with England. Worsening relations between Britain and U. S.