Confirmation of CD’s idea: AG planted seeds Ipomœa pandurata. One seed has come up and its germination is same as of I. leptophylla.
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Confirmation of CD’s idea: AG planted seeds Ipomœa pandurata. One seed has come up and its germination is same as of I. leptophylla.
Information about Ipomœa jalapa.
Apologises for his silence when Francis Darwin’s paper was read at the Linnean Society.
AG’s review of Movement in plants [Nation 32 (1881): 17–18].
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.
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].
Discusses difficulties involved in deciding which genera are protean in the light of some comments by H. C. Watson.
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.]
Discusses arrangements for American edition of Variation.
Observations on apparently inherited instinct in a dog.
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.