To B. D. Walsh 19 December 
Down. | Bromley. | Kent. S.E.
My dear Sir
I am much obliged for your interesting letter of Nov. 12—1 I hope you will meet with the success which you well deserve in solving the very curious problem of the Cynips.2
I presume that you expect that the sexual brood, whenever it appears, would be more locomotive, & thus spread the species. On the other hand, the new gall which has appeared in England recently has spread very rapidly, & yet only females have been found.3 I received your paper on the potatoe bug & it seems to me uncommonly well done.4
Sir J. Lubbock & Mr Busk called here the other day5 & neither knew or believed in the male Daphnia laying eggs.6 The former would be almost sure to have heard of it. He believes in Wagner’s case of the breeding larva of the fly.7 I shd not be very much astonished at the Daphnia case, for certain male & female Medusæ whilst sexually mature throw off reproductive buds & if these buds were encased in a shell, they might be as undistinguishable from true eggs as the ovules & buds in Aphis.8
It is curious about the post office that I some months ago was expressing much indignation at your government being so particular about writing in, & sending, single pamphlets. There are no such rules within England & it seems that they apply only to the transit from one country to the other.9
I have done no work since April owing to my health, but have just begun some easy jobs, such as counting seeds of experimental Primulas; amongst others of seedlings from John Scott’s Primulas, & these afford widely different results from what he gives.10 I mention this because I see that you quote him.11
With every good wish pray believe me my dear Sir | yours very sincerely | Ch. Darwin
Discusses a variety of subjects: Cynips, galls, potato bugs,
male Daphnia laying eggs.
His Primula experiment results differ from John Scott’s.
- Letter no.
- Darwin, C. R.
- Walsh, B. D.
- Sent from
- Source of text
- Field Museum of Natural History, Chicago (Walsh 6)
- Physical description
Please cite as
Darwin Correspondence Project, “Letter no. 4952,” accessed on 26 March 2017, http://www.darwinproject.ac.uk/DCP-LETT-4952