To Asa Gray 2 May [1856]
Summary
Suggests affinities of the U. S. flora that he considers would be worth investigating. Wants to know the ranges of species in large and small genera.
Questions AG on naturalised plants; whether any are social in U. S. which are not so elsewhere and how variable they are compared with indigenous species. Would like to know of any differences in the variability of species at different points of their ranges and also the physical states of plants at the extremes of their ranges.
Author: | Charles Robert Darwin |
Addressee: | Asa Gray |
Date: | 2 May [1856] |
Classmark: | Archives of the Gray Herbarium, Harvard University (4) |
Letter no: | DCP-LETT-1863 |
To Asa Gray 14 July [1856]
Summary
Asks whether Allegheny Mountains are sufficiently continuous so that plants could travel from north to south along them.
Hopes AG’s work on geographical distribution is progressing, as he has questions on plants common to Europe which do not range up to Arctic.
Are intermediate varieties less numerous in individuals than the varieties they connect?
Author: | Charles Robert Darwin |
Addressee: | Asa Gray |
Date: | 14 July [1856] |
Classmark: | Archives of the New York Botanical Garden (Charles Finney Cox Collection) |
Letter no: | DCP-LETT-1926 |
To Asa Gray 24 August [1856]
Summary
Rarity of intermediate varieties.
Variability of introduced plants.
Ranges of plants common to Europe and U. S.
Author: | Charles Robert Darwin |
Addressee: | Asa Gray |
Date: | 24 Aug [1856] |
Classmark: | Archives of the Gray Herbarium, Harvard University (36) |
Letter no: | DCP-LETT-1944 |
To Asa Gray 12 October [1856]
Summary
Thanks AG for the first part of his "Statistics [of the flora of the northern U. S.", Am. J. Sci. 2d ser. 22 (1856): 204–32; 2d ser. 23 (1857): 62–84, 369–403]
and for information on social and varying plants.
Would like to know number of genera of introduced plants in U. S.
Is surprised at some affinities of northern U. S. flora and asks for any climatic explanations.
Asks what proportion of genera common to U. S. and Europe are mundane.
Is glad AG will work out the northern ranges of the European species and the ranges of species with regard to size of genera.
Author: | Charles Robert Darwin |
Addressee: | Asa Gray |
Date: | 12 Oct [1856] |
Classmark: | Archives of the Gray Herbarium, Harvard University (6) |
Letter no: | DCP-LETT-1973 |
To Asa Gray 24 November [1856]
Summary
Variability of naturalised plants.
Distribution of Arctic/alpine plant species.
Limits to the northern range of plants.
Author: | Charles Robert Darwin |
Addressee: | Asa Gray |
Date: | 24 Nov [1856] |
Classmark: | Archives of the Gray Herbarium, Harvard University (5) |
Letter no: | DCP-LETT-1999 |
From Asa Gray [early August 1856]
Summary
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.
Author: | Asa Gray |
Addressee: | Charles Robert Darwin |
Date: | [early Aug 1856] |
Classmark: | DAR 165: 93 |
Letter no: | DCP-LETT-1934 |
From Asa Gray 23 September 1856
Summary
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.
Author: | Asa Gray |
Addressee: | Charles Robert Darwin |
Date: | 23 Sept 1856 |
Classmark: | DAR 165: 94 |
Letter no: | DCP-LETT-1959 |
From Asa Gray 4 November 1856
Summary
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.
Author: | Asa Gray |
Addressee: | Charles Robert Darwin |
Date: | 4 Nov 1856 |
Classmark: | DAR 165: 95 |
Letter no: | DCP-LETT-1982 |