My dear M^r. Stainton

I am going to be very unreasonable & beg from you any little information which you can give me on some points, which can hardly fail to be very doubtful.— I must trust to your kindness to excuse me.— I am working up what I have called “sexual selection”, & am sadly in want of facts in many classes of insects, especially in reference to the following points.

(1) The male Emperor & Brimstone butterflies² are much more beautiful than the females: in these cases, or in any other in which male is plainly more beautiful than female, are the males more numerous than females, or reversely?

(2) In Pamphila actæon³ the female is rather more brightly coloured than male: are there any other such cases, & especially how about inequality of number in the sexes?

(3) With Moths are the males in any cases decidedly coloured more brightly than females? Judging from Plates there is a good deal of difference between the sexes, but I know not which can be called brightest, in Oenistis quadra.⁴ In any case of well marked sexual difference in colour; how about numbers?

(4) Certain Butterflies, as the Fritillaries⁵ have wings fully as beautiful (or perhaps more) on under as on upper surface; do these, when excited & fully awake, as when in presence of female, display the lower surface more than such Butterflies with obscure under surfaces as Vanessæ?⁶ In the Emperor both upper & lower surfaces are beautiful.

(5) Have any moths wings more conspicuously coloured on lower than upper surface? I know that many moths have posterior wings gaily coloured, which are hidden when the insect is at rest.

(6) I have heard it stated that crepuscular & diurnal moths alone display fine colours, & that the strictly nocturnal moths are always obscure or white: is this true?

(7) Do the Teneinæ⁷ display well marked sexual differences of colour?

Now you will think me, I fear, the most unreasonable & troublesome man in Grt Britain; & I can hardly expect you to go seriatim through my queries. But I sh^d be truly obliged for any hints, with permission to quote you, on any of the above points, or more generally on the courtship, battles of the males,—the selection by the female of any particular male—of the mutual attachment of individual insects.— —unequal numbers in sexes—with Lepidoptera or indeed with any class, if by chance any such facts sh^d occur to your mind. Sir J. Lubbock⁸ tells me that you have made many miscellaneous observations on all sorts of insects. Now if you can forgive me & aid me you will prove yourself a good Christian as well as a great Entomologist.

My dear Sir | Yours very sincerely | Ch. Darwin

I have been sincerely grieved to hear about poor Woollaston’s affairs, in which, I am told, you have taken so kind an interest.⁹

with any gaudy butterflies, , Admiral, Peacock, Machaon¹⁰ in which both sexes are coloured with equal brilliancy are the numbers of either sex plainly in excess? I have a good many such facts from Wallace, Bates, Trimen &c with respect to exotic Butterflies,¹¹ but can find little in the few Books on English Lepidopt. which I possess.—