Encloses a cheque for £11.19.9. Will transmit £7.9.4 to Fritz Müller. Thanks for account of the sale of his books, which appears to be in a "lamentable state".

Comments on GJR’s article in Fortnightly Review ["The beginning of nerves", n.s. 24 (1878): 509–26].

Comments on "poor old" Edinburgh Review.

Wants Oxalis specimen named; is fascinated by cotyledonary movements of the genus.

Frank asked to summarise work with CD for use in JDH’s Royal Society address.

Work with A. Gray shows Colorado plants closer to Altai than to E. or W. America.

Work with J. Ball shows Moroccan plants very distinct from nearby Canaries.

JDH on Royal Commission to Paris Exhibition.

Thanks for a copy of Strasburger’s essay on ‘swarmspores’.

Before JDH discusses flora of Canary Islands CD suggests he read F. B. White’s paper [see 11707], which explains stocking of Atlantic island fauna as due to changed currents during [last, or Miocene] northern glacial period.

Thanks CD for writing machine.

Recalls visit by CD’s son [Francis].

Thanks for pt 4 of Australian orchids [1874–].

Botanical evidence is against F. B. White’s origin of St Helena fauna. JDH holds flora is S. African. Since plants must arrive before insects, if fauna is Palearctic then flora survived glacial period. Flora not Miocene since old and relic orders are absent. Suggests S. African west coastal mountains as insects’ origin.

Suggests that benzoic acid would be a deadly poison to bacteria and their allies.

Is puzzled about the use of borax as a disinfectant because in his experiments Drosera were not in the least injured by boracic acid.

Forms of flowers, translated by Édouard Heckel, is published.

Cross and self-fertilisation has only sold 450–500 copies.

Origin sells regularly; he looks forward to a cheaper edition.

Forwards letter from Victor Kennedy reporting on the growth of JT’s potatoes in W. Ireland.

Recounts the experiments on Fechner’s law he has found in Helmholz; they are on the smallest perceptible differences of illumination. Describes how to test whether plants’ responses to lights are in accordance with it.

Thanks for CD’s remarks on and agreement with his paper on history of pollination theories [see 11678].

Will shortly send his essay on the anatomy of nectaries in flowers [see 12300].

Forwards letter from George Callwell reporting what a large and disease-free potato crop JT’s seed yields.

CD is puzzled by VD’s supposed hybrid tomato. If a hybrid, it would have to result from the "direct action of the pollen of a distinct species in the mother plant". CD believes this sort of inheritance occurs in varieties (though some botanists disagree), but not for species. Suggests "bud-variation".

Did cats and dogs become pets because they are scrupulous in the discharge of their faeces? He has a pet parakeet whose behaviour supports this view.

Sends his autograph.

Wants some plants for sleep-movement observations. Has almost finished experimental work and must start sorting his notes.

EAS eagerly awaits the publication of CD’s work on heliotropism.

Sends him a paper on "Polyembryonie" [Jenaische Z. Med. & Naturwiss. 12 (1878): 647–70].