Thanks for CD’s praise of his book [see 8901].

Praises Expression.

Reports on Fritz Müller’s observations of cross- and self-fertilisation. HM will cultivate the two forms [i.e., mainly self-fertilised and mainly cross-fertilised] in the way CD has described.

He continues his observation of wild flowers. Encloses drawing of Viola tricolor with notes on its self-fertility.

Poa annua shows putative evidence of nectar secretion in grasses. He will continue observations as CD requests.

Further comments on HM’s [Befruchtung der Blumen (1873)].

Reports on insects fertilising Viola tricolor and on the fertilisation of the two wild forms [see Cross and self-fertilisation, p. 124 n., 125].

Sends a note on R. Caspary’s observations of Corydalis self-fertilisation [see Cross and self-fertilisation, p. 331].

Has begun his experiments on the self- and cross-fertilised flowers.

Fritz Müller is now working on the Brazilian honey-bees (Melipona and Trigona).

HM thanks CD for fertilisation references.

Feels CD’s and Fritz Müller’s judgments on his "Anwendung" essay [see 8313] are of highest value. Mentions some of FM’s comments.

Looks forward to second English edition of Descent.

Thanks for Insectivorous plants.

Believes Lepidoptera are of greater importance as fertilisers in alpine regions than in lowlands.

The famous stone pits of Ohningen are for sale.

Is glad CD is working on cross- and self-fertilisation; reports recent works of botanists, notably Thomas Meehan’s ["Are insects any material aid to plants in fertilisation?", Philadelphia Press 13 Aug 1875], in which the importance of cross-fertilisation is denied.

On HM’s Befruchtung der Blumen [1873].

Observations on hive- and humble-bees. Perforating habits differ in different individuals of the same species.

Comments on Fritz Müller’s article on Hedychium.

Bombus mastrucatus, an alpine bee, conforms to his observations that B. terrestris breaks open the flowers of Trifolium pratense. However, in the Alps, B. terrestris does not behave this way.

Gentiana species are adapted to lepidopteran cross-fertilisation.

He has never observed the straight line flight routes in male humble-bees that CD reports.

His last letter was in error: alpine Bombus terrestris does break into some flowers.

Thanks for Cross and self-fertilisation.

Fritz Müller has been appointed "Naturalista Viajante" of the Rio de Janeiro Museum, which will help his income greatly.

No papers on heterostyly have appeared since 1873.

Thanks CD for calling attention to a "considerable error" in his observations on Hottonia fertility [in Die Befruchtung der Blumen (1873)]. [See Forms of flowers, p. 52.]

Is pleased that CD agrees with HM’s suggestions and criticisms of CD’s work. Will undertake experiments with Viola tricolor seeds to see if they produce both large- and small-flowered plants.

Thanks HM for his review [of Forms of flowers, Kosmos 2 (1877–8): 286].

Thinks HM’s previous article was very important [Kosmos 2 (1877–8): 128–40]. CD will "heartily rejoice" if HM has explained the steps by which Rhamnus and Valeriana have been rendered dioecious.