Recalls being introduced to CD when [undergraduate] at Cambridge.

Sends CD some of his pamphlets

and expresses support of Origin.

Has discovered there are "3 sexes" in the solitary Cynips as well as social insects.

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.

Notes Louis Agassiz’s opinions on CD’s views.

Mating and sexual organs of insects.

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.

Sends his paper on "Willow-galls" [Proc. Entomol. Soc. Philadelphia 3 (1864): 543–644].

Lengthy criticism of Agassiz’s views on species as stated in his Essay on classification [1857].

Interested by CD’s trimorphism in Lythrum. Thinks some great mystery may lie in the fact that in some genera, some species are tri-, some di-, and some monomorphic, and in other genera, Apis, Vespa, Bombus, all the known species are dimorphic.

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.

Discusses several subjects, including examples of "Unity of coloration",

the origin of gall-producing poison,

Wagner’s theory of viviparous larvae,

and stridulation in insects.

Sends a reference supporting CD’s statement in Origin that flies check propagation of horses and cattle.

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

Acknowledges CD’s paper on "Climbing plants".

Mentions Asa Gray’s complimentary notice in Silliman’s Journal [Am. J. Sci. and Arts 2d ser. 40 (1865): 273–82].

His difficulty in understanding how males of Daphnia or any other genus can produce eggs. If there is no impregnation, how can there be sexual organs? Why call one form male and another female?

He has sent CD his paper on "the new Potato Bug".

Will soon send "On Phytophagi Species & Unity of Coloration". [phytophagic!?]

Complaints about practices of the English Post Office.

His current research and description of the rationale of his experiments.

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

male Daphnia laying eggs.

His Primula experiment results differ from John Scott’s.

On the "bullae" as constant, regular generic characters in Hymenoptera. Disagrees with Louis Jurine ["Observations sur les ailes des hyménoptères", Mem. Accad. Sci. Torino 24 (1820): 177–214].

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 H. A. Dubois’ attack on "Darwin, Huxley and Lyell"

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

BDW’s work [on Cynipidae].

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.

Says Jacob W. Velie wants to exchange birds’ skins with European naturalist.

Comments on meaning of "Darwinism".

Encloses papers from Practical Entomologist.

Discusses Ornithorhynchus paradoxus

and his paper on willow galls.

Mentions human skull found in California.

Balbiani’s puzzling observations on Aphis.

Sends a copy [missing] of a lecture by L. Agassiz on glaciers.

Claims worker wasps can generate additional workers in the absence of the fertile female.

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?