Discusses the origin and advantages of sexual differentiation in terms of division of labour.

Discusses the origin of the giraffe’s neck and the unsoundness of St G. J. Mivart’s view with respect to it.

Points out an error in Descent.

Discusses his paper on mimicry and natural selection [Land and Water 9 (1871): 321]. Believes natural selection tends to fix mimetic characters rigidly.

Discusses the roles of natural and sexual selection in producing mimicry, and the problem of explaining the cause of the first mimetic variation; considers the ideas of A. R. Wallace and Fritz Müller on this problem.

Wishes to use some of Fritz Müller’s observations in his paper on mimicry.

CD’s reply and Huxley’s article ["Mr Darwin’s critics", Contemp. Rev. 18 (1871): 443–76] have answered all of Mivart’s objections to natural selection as applied to man.

A. G. Butler has named the specimens sent by CD with Fritz Müller’s letter.

Sends several facts relating to sexual selection, mimicry, and hybrids.

Discusses the possibility that mimicked and mimicking forms have descended from originally allied forms and have diverged in structure but not in appearance.

Gives some information on variation of ocelli between sexes in butterfly species.

Proposes publishing a series of papers on mimicry.

Encloses a copy of his paper on mimicry [Proc. Zool. Soc. Lond. (1873): 153–61].

Asks whether large variations are more often limited to one sex than slight ones.

Has reread copy of Fritz Müller’s letter that CD sent some time ago and would like to publish the entomological observations in it.

Encloses Fritz Müller’s letter.

Is exhibiting butterflies in which variations in the female show a finely graded series. Believes dimorphism can be explained by the selection of the extremes of such a series and the consequent extinction of the intermediates.

Would like to see the Kosmos article.

Is considering producing a translation of August Weismann’s essays.

Comments on Wallace’s paper on the colours of animals and plants [Macmillan’s Magazine 36 (1877): 384–408, 464–71].

Wishes to borrow third part of Fritz Müller’s article on sexual selection in butterflies [Kosmos 2 (1877–8): 218–24].

Is forwarding material on stridulation, including Prof. Wood-Mason’s paper ["Note on Mygale stridulans", Trans. R. Entomol. Soc. Lond. (1877): 281–2], which should interest CD.

Returns Kosmos.

Thanks CD for permission to use Fritz Müller’s last letter, which contains new observations.

Encloses proof of the Entomological Society’s Proceedings for February to show the use he has made of Fritz Müller’s letter [see 11319].

Will exhibit the photos at the Entomological Society and have them identified.

Fritz Müller’s observations on relative abundance of mimicking and mimicked species.

Prof. Wood-Mason has examined Otto Zacharias’ insect photographs and confirmed the genera.

RM is going to work up Fritz Müller’s observations into a paper.

Would like to read Weismann’s essay on Daphnidae.

Fritz Müller’s paper on odours emitted by butterflies was read at last Entomological Society meeting.

Plans to produce a translation of Weismann’s Studien zur Descendenz-Theorie [1875–6] and would welcome a preface from CD.

Thanks for agreeing to write the preface for RM’s translation of Weismann.

Will arrange to meet CD when he comes to London.

Thanks for preface. When RM’s translation is complete, would like CD to expand it slightly to refer to overlap between Weismann’s observations and CD’s theories.

Is making progress with the Weismann translation.

Wonders whether Francis Darwin would give a botanical lecture at a Bayswater school.