Letter (WCP4084.4031)

[1]1, 2


March 15th. [1868]3

Dear Darwin

The only striking examples of brilliantly coloured females in the Pieridae4 are among the mimicking Leptalis and females of Pieris.5 In every other group the females are less brilliantly coloured than the males on the upper side, — except where the colours are simply yellow, in which cases the females are quite as conspicuous as the males. In the genus Thyca, which I think to some extent a protected group, the females are dusky above but the under sides of both sexes are equally brilliant as in Pl. VII. f. 3. 3a.6

[2] In the genus Tachyris when the males are brilliant the or of marked colours the females are dusky or of quite different tints. Thus T. celestina is clear ashy blue in the ♂, yellow in the ♀. (Pl. VIII. f. 6)7 but the under sides of both are of clouded pearly and ashy tints, doubtless protective.

I am delighted to see the title of your paper for the "Linnaean" on Thursday. "Specific differences between Primula veris &c."8, 9 I always thought you did not make half enough of this case. For if the Cowslip & Primrose can be proved to be producible from common parents, [3] and if, in addition to the strongly marked structural & physiological specific differences they admittedly possess, they have also the test difference of almost complete sterility, then the whole question is settled, the challenge so often thrown down is accepted, and the "origin" of a real species is proved. I sincerely hope you have settled it, & will pin your opponents to this one case.

I shall be in town from Thursday 2nd. of April till Sunday, & if you are there still shall hope to have10 [4] the pleasure of seeing you.

Have you yet any cartes of yourself? I saw a very good one in an album some time since but do not see them on sale anywhere.

Believe me | Yours very faithfully | Alfred R. Wallace — [signature]11

Page 1 is numbered 23 by the repository. Every second subsequent page has a consecutive handwritten number written in the upper right-hand corner of the page.
Annotated in the top left corner in CD's hand in red crayon "Butterfl[ie]s & protected[?] fem[a]les".
Year based on Darwin, Charles. 1869. On the specific difference between Primula veris, Brit. Fl. (var. officinalis of Linn.), P. vulgaris, Brit. Fl. (var. acaulis, Linn.), and P. elatior, Jacq.; and on the hybrid nature of the common oxlip. With supplementary remarks on naturally produced hybrids in the genus Verbascum. [Read 19 March 1868]. Journal of the Linnean Society (Botany) 10: 437-454.
A family of mostly tropical butterflies which included the genera Leptalis, Pieris, Thyca and Tachyris mentioned in the letter.
"brilliantly coloured females" and "females of Pieris" are underlined in red crayon.
An illustration of the Thyca bagoe butterfly, female, in Wallace, A. R. 1867. On the Pieridae of the Indian and Australian regions. Transactions of the Entomological Society of London, series. 3. 4 (III): 301-416, pl. VI-IX [pl. VII].
Plate VIII, the butterfly Tachyris celestina, female. See note 6.
See note 3.
"I am delighted... common parents," is crossed through by a central vertical line in ink.
The whole of page [[3]] is crossed through by a central vertical line in ink.
The whole of page [[4]] is crossed through by a central vertical line in ink.

Please cite as “WCP4084,” in Beccaloni, G. W. (ed.), Ɛpsilon: The Alfred Russel Wallace Collection accessed on 7 June 2023, https://epsilon.ac.uk/view/wallace/letters/WCP4084