Summary

Discussed observations made in 1863 of Impatiens pollen and humble-bees.

Summary

Thanks WED for measuring cowslip pollen. Sends dimorphic flowers.

Summary

Urges JS to publish on orchid pollen-tubes.

Suggests comparing stigmatic tissue of sterile hybrids and fertile parent; he would expect hybrid plant’s cell contents not to be coagulated after 24 hours in spirits of wine.

Suggests JS coat orchid stigmas with plaster of Paris for his work on rostellar germination.

Asks for list of "bud-variation" cases; CD has devoted a chapter to the subject.

Inquiries about I. Anderson-Henry’s observational competence.

Summary

Thanks Mr Beaton for his answer [to 3147].

Asks further questions on points raised in Beaton’s previous papers: whether crossing white and blue varieties of Anemone apennina produced many pale shades; whether the Mathiola incana and M. glabra which crossed freely were artificially or naturally crossed.

CD is delighted by Beaton’s assertion that "not a flower in a thousand is fertilised by its own immediate pollen".

Recounts his experiments with Leschenaultia formosa to show insect fertilisation.

Summary

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.

Summary

Enthusiastic about JS’s work on Passiflora self-incompatibility.

CD quotes JS on rostellar pollen germination [in "Fertilisation of orchids", Collected papers 2: 77–8]. H. Crüger attributes it to ants’ carrying stigmatic secretion to pollen.

Homomorphic cowslip seedlings are, sadly, showing variation.

Summary

Describes the difficulties of crossing papilionaceous flowers. Believes the lack of success is a consequence of the need for early castration and successive applications of pollen on the stigma. Gives details of a method he has used to cross such flowers successfully.

Summary

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].

Summary

In his last letter FM told CD about four flowers of Lagerstroemia that he had fertilised with the yellow pollen of another variety or species and which had subsequently fallen off. He has now repeated the experiment using the yellow pollen of a different variety and successfully produced good fruit as large as that fertilised with green pollen.

Summary

Sends drawings of atypical Geranium and honeysuckle pollen-grains. Would they produce variation in seedlings?

Summary

Thanks for suggestion to try effect of dry heat on pollen and for other new information on pollen. Will begin new experiments soon, hoping to cure hay-fever.

Summary

Sends Primula scotica and P. farinosa.

So far cannot fertilise Gongora atropurpurea although it is similar to Acropera luteola.

Experimenting on intergeneric hybrids to test CD’s view that sterility is not a special endowment.

Scott’s personal history.

Acropera capsule grows.

Plans for experiments CD has suggested on Primula, peloric Antirrhinum, and Verbascum.

Asks about Gärtner’s experiments on maize.

Aware of Anderson-Henry’s failures.

Through kindness of J. H. Balfour and James McNab, enjoys facilities for research. JS is in charge of the propagating department. Balfour almost engaged him to be superintendent of the Madras Horticultural Garden.

Summary

Reports the observations of Hermann Crüger and John Scott that fruit is set by orchids whose flowers never open and that pollen-tubes are emitted from pollen-masses still in their proper position. These cases convince CD that in Orchids he underestimated the power of tropical orchids to produce seed without insect aid but he is not shaken in his belief that the structure of the flowers is mainly related to insect agency.

Summary

On what kind of moth have pollen-masses of orchids been found cohering? Will ask Mr Parfitt if he is certain he recognised pollen-masses of bee orchid. CD thinks green masses were those of true Orchis.

[In P.S., having received a letter on subject from HTS responding to same query published in Gard. Chron. 9 June 1860:] It is extremely curious that the same moth has been found with pollen-masses in two parts of England.

Summary

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.

Summary

Has read CD’s long letter on Lythrum and agrees with it. Is examining the pollen of the different types.

Summary

[Outline sketches of pollen from long- and short-styled yellow cowslips and from a red cowslip.]

Summary

Lythrum. Wants to examine fresh flowers of Lythraceae. Lythrum salicaria has interested him very much.

Microscopes.

Asks whether JDH can think of plants that have different coloured anthers or pollen in same flowers (as in Melastoma) or on same and in different plants as in Lythrum. Would be a safe guide to dimorphism.

Observation of action of pollen in Linum grandiflorum.

Summary

Discusses the possible explanation of why fly-orchid plants in a correspondent’s garden had no pollen-masses removed while Orchis maculata had all of its pollen-masses removed. CD points out that different orchids are fertilised by different insects. The insects needed to fertilise the fly-orchid may not have inhabited the site of the correspondent’s garden.