Thanks CD for the copy of Orchids and papers on Linum and Lythrum [Collected papers 2: 93–105; 106–31].

Intends to travel to the River Itajahy and will make observations on climbing plants. Is not sure whether Dalbergia is a winding plant.

CD has changed FM’s whole perception of nature.

CD has helped him to understand distribution of coastal flora.

The vegetation on Desterro is changing.

Louis Agassiz is seeking evidence against transmutation in the distribution of the fish in the Amazon.

Thanks CD for Journal of researches.

Insect genus Elater is an exception to the rule that all luminous organs give out a green light.

Gives some observations on climbing plants at Itajahy.

His study of orchids has convinced him of the value of CD’s book.

Thanks CD for German translation of Origin.

Droughts over the summers have brought about changes in the numbers of plants and animals in the area. The small quantity of Orchestia darwinii that has survived the changes no longer includes two previously common male forms. Great changes also take place without such unusual physical conditions. The disappearance of a briefly abundant bryozoan in local caves has made way not for the return of original bryozoan inhabitants but for a completely new fauna.

Gives some observations on orchids and on some plants which seem to be dichogamous.

Discusses dimorphism of Oxalis; one form has 99% sterile anthers. Has found three kinds of fertile anthers.

Sends his observations on sterility of Eschscholzia,

on Oxalis,

and on recently found dimorphic plants.

Sends specimen of Hedyotis [see Forms of flowers, p. 133].

Gives observations on orchid ovules ripening long after blooming.

Infertility with own pollen sometimes does and sometimes does not indicate dimorphism; gives observations on Ximenia, Eschscholtzia and Oncidium flexuosum.

Describes some striking seeds eaten by birds,

and some new dimorphic species.

Variation in Thillia.

Confirms CD’s suspicion that the lancet-fish [Amphioxus] lives in competition with invertebrates: it shares its habitat with a similar-looking Ophelia, which is quite unlike other annelids, just as the lancet-fish is unlike other fishes.

Describes his experiments in fertilising Oncidium flexuosum and comparison with Notylia.

Has been examining Catasetum.

Encloses seeds of two species of Gesneria and describes hairs in the seed capsule. Hairs in other plants seem to have a different function.

Starting tomorrow for a botanical excursion on the Continent.

Thanks for CD’s letter inquiring about capsules produced by the Maxillaria with larger pods [see 5331]. Gives descriptions of Maxillaria and of the other Vandeae.

Describes Oncidium flexuosum.

Tells of botanical results of recent excursion to the German colony Theresopolis. Brought home fine collection of living orchids.

Reports observations on fertility of orchids he has self-pollinated and crossed with pollen of other species.

Cites cases of difference in coloration between the sexes of some species of Crustacea, annelids, and spiders.

Discusses dimorphic plants and self-sterility.

Outlines some experiments involving the crossing of different species of orchids.

Encloses extract from Carl Claus, Die freilebenden Copepoden [1863].

Discusses dimorphism in plants, especially the Rubiaceae.

Gives observations on orchids; notes varying degrees of self-sterility and a varying success at crossing distinct species.

Mentions local ferns he is collecting

and considers the phenomenon of apparently mimetic plants.

Thanks CD for sending F. H. G. Hildebrand’s book on fertilisation [Die Geschlechter-Vertheilung bei den Pflanzen (1867)]

and J. D. Hooker’s "Lecture on insular floras".

Describes work on Rubiaceae, Oxalis,

and on crossing orchids. Lists crosses made.

As for CD’s query concerning sexual differences among invertebrates, he gives the case of the local amphipod, Brachyscellus diversilor. Male differs in shape of antennae and coloration.

Also mentions local fish in sea near Sta Catharina which emits melodic tone to attract females.

Has CD ever considered that the colour of seeds of Amarantaceae would attract the attention of birds?

Describes case of a climbing Chamissoa of the local flora.

Thanks CD for sending him copy of Variation.

Describes results of his brother’s [August Müller] experiments on effect of climate on maize.

Like ancestors of horses, young tapir is also striped.

His opinion of Pangenesis.

On relative proportion of sexes in marine animals [sthg missing!?] Crustacea.

Sexual differences.

Music of Cicadae.

Again thanks CD for trouble in arranging for translation of Für Darwin.

Sends addition answering critics of his idea of insect metamorphosis [see Möller ed. 1915–21, 1: 259].

Agrees with Charles Lyell’s suggested English title "Facts and arguments in favor of Darwin", although perhaps more accurate to call it "Darwinism tested by Carcinology" or "Carcinology as bearing on the origin of species".

Says any profit should go to CD for his trouble and expense with the translation.

Thanks for seeds of Eschscholtzia.

Gives observations on number of climbing plants, including Dilleniacea, Marantacea, Catasetum.

Will repeat CD’s experiments on dimorphic and trimorphic plants.

Auditory organs of Orthoptera; stridulation in lamellicorn beetles.

Writes on various observations and discoveries on dimorphic and trimorphic plants.

Gives details of some crossing experiments with Eschscholzia.

Describes the grass Streptochaeta, which FM believes to be a primitive grass.

Relates some observations on maize that are well explained by Pangenesis.