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.

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?

Summary

Rarity of intermediate varieties.

Variability of introduced plants.

Ranges of plants common to Europe and U. S.

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.

Summary

Variability of naturalised plants.

Distribution of Arctic/alpine plant species.

Limits to the northern range of plants.