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.

JDH writes to Sir WilliamTurner Thiselton-Dyer about John Reader Jackson [Keeper of the RBG Kew museums] attending the Paris Exhibition [Third Paris World's Fair]. JDH would also like to take Jackson to the Jardin des Plantes. JDH has attended a deputation from the Colonies to the Prince [Princes of Wales, later Edvard VII] offering him the colonial collections from the exhibition to establish a colonial museum. These collections will be stored in the South Kensington galleries [Victoria and Alber Museum] temporarily which means that RBG Kew will not get the Douglas fir but they wil get a Xanthorrhoea, a tree fern stem probably of Alsophilia cooperi & some other unspecified things. JDH has seen Brand's[?] collection of woods but was not impressed by the display. JDH visits the exhibition daily& is also often at the Embassy with the Prince, who sympathises with keeping RBG Kew shut [to the public during the mornings] but suggests a compromise. JDH still needs to see the horticulture diaplays at the exhbition. Also, to meet with M. Pierre about publishing Pierre's collections with government assistance, about which Joseph Decaisne is sceptical. The balls or 'fetes' at Versailles & the Ministries have been badly organised, JDH [& his wife Hyacinth Hooker] spend the evenings with the Regnals[?], relations of Hyacinth's & the Symonds family. They have been to the Hippodrome. They will catch the Boulogne train home. JDH is returning the proofs of the BOTANICAL MAGAZINE to Reeve, the publishers. William Munro is leaving for Dieppe having been disappointed with the grasses at the Jardin des Plantes. JDH reports some gossip about John Forbes Watson leaving the India Office.

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].

No summary available.

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.

JDH writes to Sir William Turner Thiselton-Dyer about his time in Paris. He [& his wife Hyacinth Hooker] could not stay at the Hotel de Famille & have been forced to take rooms at an inferior establishment; Hotel l'Amiral. They have been to the Exhibition [Third Paris World's Fair] where JDH admired the Japanese edibles such as Pteris aquilina in syrup, also a collection of bamboos, the Englsih glass & French artificial flowers but he got bored with the amount of porcelain on show. They have also been to Cluny, a prize giving at the Palais d'Industrie & briefly to an overcrowded ball at the 'Ministre of Agriculture & Commerce'. JDH will go to a speech by the exhibition jurors & to see the Prince at the British Embassy. JDH has met with William Munro & together they will go to the Jardin de Plantes to visit Joseph Decaisne. JDH & Hyacinth dine daily with Mr & Mrs Ragnel, Hyacinth's aunt. Due to rain they will not attend the ball at Versailles. JDH approves of the improvements being made in Paris but finds the city very noisy, smelly & poorly designed for pedestrians. The Palais Royal does not have the quality shops it used to, good jewellery especially is now to be found further West. JDH is worrying about his [Royal Society] Address, he asks WTTD to help him by preparing a list of significant scientific developments. In a post script JDH ads that the Duval Bouillons are: 'so full one cannot get near them'.