No summary available.

Thanks RM for information on case of hexadactyly [see RM’s paper, "Hexadactylism", Land and Water, 11 March 1871, p. 179.

Mentions the difficulties in explaining the separation of sexes and Carl Nägeli’s view that the sexes of plants were primordially distinct.

Has been experimenting for five or six years to demonstrate that the benefits of crossing are the same as those derived from a slight change of conditions.

Discusses the problems of mimicry as related to natural selection; the general variability of colour as a character; and the conditions necessary for natural selection to fix firmly a character.

Encloses a Fritz Müller letter speculating that organisms respond to certain colours because of the prevalence of those colours in their environment.

Invites RM to keep some specimens as long as he wishes.

Recalls vaguely the mention of a butterfly species in which the male alone is mimetic.

Feels it would be worth while but difficult to investigate mimicked and mimicking forms for structural similarities that would indicate a closer alliance in the past.

Thanks RM for note on ocelli.

Thanks RM for his paper on mimicry.

Cannot answer RM’s query because he believes it impossible to define large variations.

Believes monstrosities are generally injurious and are not often, if ever, taken advantage of in nature.

Is doubtful about the publication of Fritz Müller’s letter after so long an interval.

Thinks the facts in Fritz Müller’s letter could be published.

Recommends August Weismann’s essay on dimorphism ["Über den Saison-Dimorphismus der Schmetterlinge", Studien zur Descendenz-Theorie 1 (1875)]

and has no doubt that intermediate forms could be eliminated as RM suggests.

Does not think Fritz Müller can object to anything RM has said in his essay.

Has alluded to colour preference among butterflies in Descent [1: 400–1].

Interesting article by Fritz Müller on sexual selection in butterflies, Kosmos [1 (1877): 388–95].

Thinks Weismann would welcome a translation.

Was dissatisfied with Wallace’s article.

Hopes RM finds a publisher [for his translation of Weismann’s Studien].

Good article by Fritz Müller in Kosmos supporting August Weismann’s views on caterpillars.

Is dispatching December number of Kosmos.

Will read the discussion on stridulation that RM mentioned.

Thinks there can be no objection to RM’s using a Fritz Müller letter [see 11319].

Thanks RM for his interesting paper ["Entomological notes bearing on evolution", Ann. & Mag. Nat. Hist. 5th ser. 1 (1878): 155].

Asks RM to send a copy of the Entomological Society’s Proceedings to Fritz Müller.

Thinks RM may like to see the enclosed [Fritz Müller letter].