Studying self-sterility, particularly in Oncidium, where abortion occurs consistently but stigma functions normally. His hybrid orchid crosses show sterility occurs capriciously. Thus it is not a "special endowment".

Disputes Asa Gray’s and Hermann Crüger’s view of rostellar germination.

Doubts absolute sterility of Catasetum.

Disappointed by results with homomorphic cowslips.

Supports, in his orchid paper, CD’s view that sterility occurs at random [Trans. Bot. Soc. Edinburgh 7 (1863): 543–50].

Cannot get his Drosera paper published [abstract in Edinburgh New Philos. J. 2d ser. 17 (1863): 317–18].

Sends Passiflora paper [see 4485].

Sends seeds of peloric Antirrhinum crossed by normal form and sends results of his experiments [table of crosses].

Position as Curator allows no time for experiment.

Describes plans for vast new layout of Calcutta Botanic Garden according to natural orders.

Himalayan and Scottish plants are doing well.

Hopes to experiment on temperate plants in tropics, to test CD’s views of migration during glacial periods.

Sends observations on acclimatisation of English cultivated plants.

Leersia CD sent are growing and fertile.

Observations on expression and colour of beard and hair in natives of India.

Praises JS’s experimenting.

Has he ever studied the relative fertility of varieties? CD very interested in this subject.

Discusses Acropera.

Wants to quote JS on Zea [Variation 1: 321].

CD sends his Primula paper [Collected papers 2: 45–63].

Thanks JS for orchid paper [Trans. Bot. Soc. Edinburgh 7 (1863): 543–50]. JS presents excellent new facts on sterility of orchids.

His argument that coloured primroses are not hybrids is good, as is idea of discovering primrose parentage by breeding for colours.

Thanks for Cross and self-fertilisation.

His work on poppy varieties confirms increased vigour with crossing.

JS is carrying out opium poppy experiments CD suggested. He is busy with opium duties. Observing many fields of poppies, day and night, JS finds them remarkably free of insects. Believes they are wind-pollinated and that varieties have prepotent pollen since he has shown they do not cross naturally.

Plans to send a paper on Cyclosis to Linnean Society.

Comments on various species of Lagerstroemia.

In the series of opium poppy intercrosses made at CD’s suggestion, JS has learned that the reason they failed to intercross was the absence of insects at the period of their flowering.

CD is mistaken in considering Acropera unisexual, with only male flowers [Orchids, pp. 203–10]. JS has successfully fertilised two A. loddigesii flowers. One is ripening. Dissection of the other shows the pollen accomplishes fertilisation without contacting any stigmatic surface. Abortive ovules found in flowers that did not become fertilised when pollinated. JS suggests Acropera has both unisexual male and hermaphrodite flowers.

Appreciates CD’s acknowledging his letter and his comments on Acropera. Will send CD the Acropera capsule which is now maturing.

Experimenting on vegetable parthenogenesis.

Structure of Acropera.

JS does not fully accept natural selection.

Has never raised oxlips from cowslips or primroses; reports of such must be cases of crossing.

Discusses relative fertility of varieties, self-fertility of hybrids, and plans for experiments on enhanced hybrid fertility.

JS not ready to publish on Primula.

Some of his objections to natural selection are based on belief that plants with separate sexes are less variable than those in which sexes are confluent (as in ferns).

Sends his paper on fern varieties [Edinburgh New Philos. J. 2d ser. 16 (1862): 209–27].

Will soon read paper on Drosera irritability [Edinburgh New Philos. J. 2d ser. 17 (1863): 317–18].

How does CD explain capricious distribution of irritability among plants?

P. scotica’s non-dimorphism is native.

Beginning Laelia experiments shortly.

Thanks for Journal of researches and Origin.

Thanks CD for comments on his fern paper [see 3847 and 3853]; has great difficulty in expressing his ideas.

Discusses inheritance and variation.

Asks CD for an account of the experiments he would like JS to perform.

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.

Experiments to cut Laelia stigma from rostellum and then to fertilise rostellum are baffled by "a latent instinctive power". Somehow the pollen-tubes find their way to the style.

Suggests CD study variation in ferns.

Sends Acropera capsule for CD to dissect.

Will try to raise Acropera from seed (never done before in Britain) to examine its sexual forms.

Studying primroses, parthenogenesis, and reproduction of some cryptogams.

Received maize varieties from CD.

JS criticises natural selection as based on an innate "continuously watchful selective principle".

Seeks seed of wild Rocky Mountain maize.

What is CD’s view on origin of maize?

Seeks information on self-sterility of Passiflora and Lobelia.

Weeping habit of trees.

Intended to say bisexual plants presented more established varieties than unisexual, not that they are more variable.

Explains his opinion that homomorphically fertilised Primula will produce only their own form. Is trying homomorphic crosses with different coloured Primula varieties.

Asks to read Asa Gray’s 2d review of Orchids.

Has finally successfully fertilised Gongora, but it was done by unnatural means.

Thanks for CD’s answers on Passiflora

and Asa Gray review.

Has observed gradation of sterility in Oncidium species.

Has observed rostellar germination and fertilisation in Laelia. The latter was prevented in Bletia by covering the stigma with plaster of Paris.

Gongora atropurpurea capsules are swelling.

Thanks for CD’s Linum paper [Collected papers 2: 93–105].

Has not published much because he would be ignored as a gardener; hence he is looking for a foreign appointment.

Has prepared orchid sterility paper at CD’s suggestion [Trans. Bot. Soc. Edinburgh 7 (1863): 543–50].