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Darwin Correspondence Project

From Octavius Pickard-Cambridge   17 February 1874

Bloxworth Rectory | Blandford

Febry 17. 1874

My dear Sir

I am most pleased to give you the information you ask—1 The subject of the small size of some male spiders was first spoken of by myself in a paper on “The numerical proportion of sexes among spiders” Zoologist, June 1868. p. 1240.2

It is again referred to (and figures given of the sexes of two species) in “Proceedgs. Zool: Socy 1871. pp. 620–21. pl. 49”, in a paper on “Some Arachnida collected by C. Collingwood MD. in the China Sea”—3

There is a point worth noting (in connection with the subject of the males of spiders) benoted in the latter paper p. 619. I allude to the form of the palpal Crochet, or Conjoncteur of French Araneologists shewing the danger the male may run in fulfulling his office.4

May I take this opportunity of mentioning to you a doubt I have felt in regard to the theory of “Sexual Selection”—? If I am right in my apprehension of this, it is “that male peculiarities of structure are attributable to female appetency or predilection”!5 It has occurred to me that, curious male structures might better be accounted for by “Natural Selection” simply.

It seems to me that there is undoubtedly something in the male organization of a special & sexual nature, which of its own vital force developes the remarkable male peculiarities so commonly seen, and of no imaginable use to that sex. In as far as these peculiarities shew a great vital power, they point out to us the finest and strongest of the sex, and thus shew us which of them would appropriate to themselves the best, and greatest number of females, and leave behind them the most numerous progeny; and here would come in the application of “Natural Selection”. for the possessors of the greatest vital power being those most frequently produced and re-produced, the external signs of it would go on with a constantly increasing exaggeration; only to be checked when they became really detrimental to the individual.

I do not know if I have made myself intellegible, but I have fancied that looking at it as above, there would be no reason to resort to “Sexual Selection” to account for male sexual peculiarities of structure whether of the nature of what we usually term ‘ornamental” or not. Of course what I have said presupposes an unexplained, and perhaps unaccountable, element in the sexual nature of the male, more powerful than that of the female— if this be granted the rest would seem to follow.

If the many calls upon your time might allow you to give me your ideas on the above I shd esteem myself much honoured.

I am faithfully & truly | your’s O. P. Cambridge

Chas. Darwin Esqre

CD annotations

2.1 “Proceedgs.... 49” 2.2] underl red crayon
3.2 p. 619] underl red crayon
4.3 attributable … predilection”! 4.4] double scored red crayon
5.2 which … seen, 5.3] scored red crayon; ‘so many ♂ without such’ pencil
Top of letter: ‘Why Display?’ red crayon


CD’s letter to Pickard-Cambridge has not been found.
O. Pickard-Cambridge 1868.
CD quoted from O. Pickard-Cambridge 1871 in Descent 2d ed., p. 273. Cuthbert Collingwood was ship’s surgeon and naturalist on voyages of exploration in the China seas in 1866 and 1867 (ODNB).
Pickard-Cambridge noted the existence of a corkscrew-shaped spine projecting from the palpi of the male of Nephila rivulata (now Nephilengys malabarensis), which he thought was probably intended for adhering to the female during mating, in O. Pickard-Cambridge 1871, p. 619. Crochet: hook (French).
See, for example, Descent 1: 272–3.


Criticises sexual selection theory. Supports natural selection.

Gives CD references on proportion of sexes in spiders.

Letter details

Letter no.
Octavius Pickard-Cambridge
Charles Robert Darwin
Sent from
Source of text
DAR 161: 7
Physical description
5pp †

Please cite as

Darwin Correspondence Project, “Letter no. 9299,” accessed on 18 June 2019,

Also published in The Correspondence of Charles Darwin, vol. 22