Thanks BDW for new facts about Anthocaris [see 6156].
Asks BDW to observe stridulation apparatus in male and female lamellicorns.
Down. | Bromley. | Kent. S.E.
June 9. 1868
My dear Sir
I am very much obliged for your letter of May 1
It has occurred to me that you might perhaps whilst collecting, observe one subject for me without much trouble. I have lately been examining the stridulating apparatus in lamellicorns; & I am surprized to find it in a totally different position in Oryctes & Geotrupes. I have not yet examined enough specimens, but the organ seemed more developed in the male Oryctes than in the female. Now if you catch any m. & f. lamell. will you observe whether the f. can squeak or grate, or whether it does so louder than the male. If so, could you send me a m. & f. named. Does Trox exist with you? As far as I can make out with dead specimens, it grates by rubbing the spinose tibia of middle legs on the edges of the Elytra; & it seems to have no proper stridulating apparatus.
Many thanks for your Report. I agree with your criticism on my expression; as far as I remember I used it merely because others might make a similar objection.
This Report of yours must have cost you an immense quantity of labour. I am still at work & shall continue so for many months on the sexual differences of animals.
With all good wishes believe me | my dear Sir | yours sincerely | Charles Darwin
- f1 6236.f1See letter from B. D. Walsh, 1 May 1868. Anthocaris (a butterfly genus) is now spelled Anthocharis.
- f2 6236.f2CD reported Walsh's speculation on the colours of some Anthocharis species in Descent 1: 393--4.
- f3 6236.f3See Descent 1: 378--85, especially pp. 380--1; see also letters from H. W. Bates, 20 May 1868 and 28 May 1868, letters from E. W. Janson, 25 May 1868 and 4 June 1868, and letter to H. W. Bates, 21 May . Oryctes and Geotrupes are genera of Coleoptera (families Dynastidae and Geotrupidae, respectively).
- f4 6236.f4On sexual differences in the power of stridulation in Coleoptera, including Oryctes, see Descent 1: 382--4.
- f5 6236.f5In Descent 1: 380, CD reported that he had `failed to discover the proper organs' of stridulation in Trox sabulosus.
- f6 6236.f6CD refers to Walsh's `First annual report on the noxious insects of Illinois' (Walsh 1867b). For Walsh's criticism, see the letter from B. D. Walsh, 1 May 1868 and n. 11.
- f7 6236.f7CD's work on sexual selection in animals was published in Descent.