Thanks for letter and memoirs.

Suggests a "rather hopeless experiment" of introducing poisons into tissues of plants on the chance that monstrous growths may be produced.

Discusses Agassiz’s misrepresentations of his views and J. D. Dana’s "wild notions".

The reception is friendlier from younger scientists in France, and many of the best men in Germany.

Sends J. O. Westwood’s direction.

Comments on BDW’s papers ["On certain entomological speculations of the New England school of naturalists", Proc. Entomol. Soc. Philadelphia 3 (1864): 207–49; "On insects inhabiting the galls of certain species of willow", ibid. 3 (1864): 543–644]; much is new to CD.

Asks about wide-ranging insect genera,

Rocky Mt. wingless insects,

willow hybrids,

galls,

and other subjects.

Thanks BDW for his interesting letter [4839] and for the case of Panagaeus, a genus almost sacred to him since Cambridge days.

Discusses a variety of subjects: Cynips, galls, potato bugs,

male Daphnia laying eggs.

His Primula experiment results differ from John Scott’s.

CD has followed Lyell’s advice and avoided controversy over Origin but encourages BDW to attack S. H. Scudder and others who argue foolishly or misquote him.

On various subjects: Dana’s misquotations,

H. J. Clark’s book Mind in nature [1865],

BDW’s Cynips experiments, galls,

Balbiani’s paper on aphids ["Sur la reproduction et l’embryogénie des pucerons", C. R. Hebd. Acad. Sci. 62 (1866): 1231–4, 1285–9, 1390–4].

Claus and other Germans testing CD’s views of variability in common lower animals.

Balbiani’s puzzling observations on Aphis.

Thanks for Agassiz’s Lectures. Lyell does not believe a word about glacial action of any kind in lowlands of Brazil. Agassiz’s view of glacial movement has been given up by physicists.

Is not sure he thinks so much of BDW’s argument in his last paper as of some others he advanced. Is BDW sure Lucanidae use jaws for holding female in copulation rather than for fighting other males?

Is sending a copy of Variation [to be published in a few days]. It cost more labour than it is worth.

George Darwin is Second Wrangler.

Requests entomological data on sexual selection, especially proportions of sexes.

Sends Queries about expression with note: "a great hobby of mine".

Has looked through BDW’s papers and finds heaps of facts on sexual differences. Asks questions on sexual differences in particular species.

BDW’s letter [6051?] and his notes are a "mine of wealth". The negative evidence is of much value. Sexual selection is a perplexing subject – finds he "must make the best of a rather bad job".

Sends copy [of Variation].

Thanks BDW for new facts about Anthocaris [see 6156].

Asks BDW to observe stridulation apparatus in male and female lamellicorns.

Thanks BDW for pamphlets [by S. H. Scudder and J. D. Caton].

His information about Cicada is of extraordinary interest. Discusses stridulation organs which certainly sometimes differ in the sexes. CD would be curious to know if "dumb" Cicada can breed.

Thanks BDW for extracts about "drumming" [of male Cicada to attract females].

Asa Gray and Hooker doubt that 13–year and 17–year Cicada forms should be considered distinct species. CD is inclined to agree with them.

Suggests observations be made of ratio of females to males in the rarer form.

Glad BDW has proved his case on dimorphism of Cynips.

Interested in galls

and BDW’s Cicada articles [Proc. Entomol. Soc. Philadelphia (1864)].