Ludwig Rütimeyer thanks CAB for the skull of a Chillingham cow, and thinks it may belong to the Primigenius race.

Thanks for photograph, charmed by Mrs Huxley’s letter.

Regrets THH cannot do the popular work on zoology.

Has heard THH wrote leading article in last Reader ["Science and ""church policy"" ", 4 (1864): 821].

"I return your letter to [William] Sharpey." Grandest eulogium CD has received.

Concerning the proposed translation of K. F. von Gärtner’s Bastarderzeugung (1849).

Has finished long paper on "Climbing plants". Prefers sending it to Linnean Society if Bentham does not think it too long.

For New Zealand flora [1864–7] CD suggests JDH count plants with irregular corollas and compare with England.

Does not quite agree about Reader.

Is Tyndall author of piece on spiritualism?

CD’s illness diagnosed as "suppressed gout".

Thanks TCE for information about breeding

and for his promise to measure feet of otter-hounds [see Variation 1: 39–40].

"Read a letter from Mr Darwin expressing his regret that the state of his health would not permit of his writing an Introductory Chapter to the Translation of Gaertner’s work [Bastarderzeugung im Pflanzenreich (1849)]."

Pleased to learn that HD has resumed research on Anoplura.

Are Chiloe pediculi a distinct species?

Do lice differ on different races of humans?

Is there evidence supporting Mr Marshall’s statement about Polynesian lice?

Asks that the long paper that he is sending for the Society be acknowledged when received.

"Climbing plants" sent off.

Encourages JDH to include notes on gradation of important characters in Genera plantarum or to write a paper on the subject. Has given prominence to gradation of unimportant characters in climbing plants. Believes that it is common for the same part in an individual plant to be in different states. Same may be true of important parts – for example position of ovule may differ.

Two articles in last Natural History Review interested him; "Colonial floras" [n.s. 5 (1865): 46–63]

and "Sexuality of cryptogams" [n.s. 5 (1865): 64–79].

Fact of similarity of orders in tropics is extremely curious. Thinks it may be connected with glacial destruction.

Leo Lesquereux says he is a convert for the curious reason that CD’s books make birth of Christ and redemption by grace so clear to him!

"Not one question [for JDH] in this letter!"

Criticises Duke of Argyll’s address [to the Royal Society of Edinburgh (1864)] and demurs on Argyll’s "new birth" theory.

Agrees with CL on beauty.

Enjoyed hearing of Princess Royal’s discussion [on Darwinism].

CD’s illness.

CL’s advice on chapter [of Variation] on dogs was excellent.

CD would be proud to be one of EW’s series [Portraits of men of eminence (1863–7)]. If he goes to London in the summer he will call on Mr Edwards [the photographer].

Thanks JEG for congratulations [on Copley Medal?].

Mentions JEG’s illness.

Returns [Andrew] Murray’s paper;

especially values HD’s note that the same species of lice infect the different varieties of fowl, pigeon, and dog. Further queries about the relationship of the same species of pediculi to different domestic varieties.

Commends ARW’s papers on parrots

and on the theory of geographical distribution [see 4750].

Wild pigs in Aru Islands must have been introduced and later ran wild. Does ARW have an opinion on the subject?

Orders that one of CD’s Porto Santo rabbits be killed and sent to him.

Asks whether ADB has got young from mating these with females of other breeds.

Exchange of photographs.

Aru pigs present perplexing case, whether wild or domesticated.

Hugh Falconer’s death great loss to science.

His own health has been especially bad this last week.

Is glad MTM is going to experiment on Passiflora.

Is grieved to hear that John Scott has been inaccurate but cannot think he recorded, in his paper, experiments that he never made [see 4485].

He has finished MEW’s work on hybrid willows [Die Bastardbefruchtung im Planzenreich (1865)] and sends his thanks. The extreme frequency of hybrid willows is new to CD, and he finds the explanation of their numbers in certain locations ingenious.

Comments on the criticism of Gärtner’s view of reversion

and the differences between MEW and Naudin.

CD now has doubts regarding his own view that hybrids are sterile from not being perfectly accommodated to their conditions of life.