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.

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

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.

Reports results of crosses between the two forms of Viola tricolor: 1. Female small flower crossed with male large flower yields all small flowers (cleistogamous self-fertilisation suspected); 2. Male small flower crossed with female large yields intermediate flowers; 3. Large flower crossed with large flower yields self-sterility symptoms.

Thanks CD for his efforts to get HM’s book, Die Befruchtung der Blumen [1873], translated into English. [See Fertilisation of flowers, translated by D’Arcy W. Thompson, preface by C. Darwin (1883).]

Will soon return to his observations on insects in general and bees in particular.

Seventieth birthday greetings.

HM’s teaching methods and his ideas are under attack in Germany along with the works of Ernst Krause.

Fritz Müller’s daughter has committed suicide.

HM’s son will visit CD when he comes to London.

Is glad CD approves of his judgment of G. Bonnier’s paper on nectaries [Gaston Bonnier, "Les nectaires", Ann. Sci. Nat. (Bot.) 8 (1879): 5–212].

Movement in plants has shown him CD’s research method: 1. Find a fundamental idea of great generality (circumnutation); 2. Pursue it everywhere with observations and experiment; 3. Conduct special observations which undo any doubt of generality.

Fritz Müller suffered moderate damage in Brazilian flood.

Continued praise for the universal importance for botany of Movement in plants.