From W. F. Kirby   8 September [1863]

Dear Sir

I must apologize for not answering your letter of July 9^th long before, but I was unable to attend the August meeting of the Entomological Society, and consequently never received it till yesterday.¹ I am very glad you approve of my paper, but it is a very imperfect sketch for want of more extensive materials.² There is a slight error in my remarks on the genus Papilio, as the number of described species is (in round numbers) not 300 but 400.³ I think M^r Wallace once remarked to me that the depth of the sea between Corsica and Sardinia and the main land of Italy proved that they had long been separated.⁴ M^r Doubleday⁵ tells me that Coenonympha Typhon (which I regard as a distinct species from C. Davus, though he does not) gradually becomes paler and paler as it advances north till in Scandinavia and the northern islands of Scotland it is almost white and immaculate forming the variety Isis of Thunberg.⁶ And there is a whitish Coenonympha nearly related to this in the British Museum from California. C Davus (or rather C Typhon I imagine, which is the commoner form) occurs in Amoorland.

On referring to Menetries I find that two or three forms of Isis occur in Amoorland, and after examining a large number of specimens, he is of opinion that it is only a northern form of Davus (Typhon)⁷ I think M^r Doubleday once told me that Isis occurred in Iceland, but I am not certain. The most perplexing question in the geographical distribution of butterflies is how to account for that of Pyrameis Atalanta and Callirhoe. I suppose that while Atalanta, a species of gigantic power like all of its genus was establishing itself on the continent of Europe and Africa, the Canaries were separated from the mainland so as to prevent its crossing over and crushing out Callirhoe. I had suggested this in my paper, but struck it out at the suggestion of M^r Bates who kindly looked it over before I read it, and thought the hypothesis too fanciful.⁸ Still this would not account for the occurrence of Atalanta in North America, as I have no evidence of its having occurred east of Asia Minor, and if it occurred in Siberia, such a conspicuous insect must have found its way into some of the excellent Russian works on the Lepidoptera of Northern Asia. To be sure Cramer says that it occurs in China,⁹ but if it occurs in Northern Asia at all, it must be very rare, and no dependence whatever can be placed in localities given for insects by the old authors, some of whom used the phrase “ab Indiis” as equivalent to “exotic”¹⁰

With every wish for the success of your series of works on species,¹¹ | Believe me, dear Sir | Yours very truly | W. F. Kirby

PS M^r F. Smith¹² will tell you there is a humble-bee (Bombus Smithianus) peculiar to the northern Islands of Scotland   I forget which