for the Royal, it would, of course, appear intolerably presumptuous to propose for the Copley also.

LETTER 40. TO T.H. HUXLEY. Down, June 10th, 1855.

Shall you attend the Council of the Royal Society on Thursday next? I have not been very well of late, and I doubt whether I can attend; and if I could do anything (pray conceal the scandalous fact), I want to go to the Crystal Palace to meet the Horners, Lyells, and a party. So I want to know whether you will speak for me most strongly for Barrande. You know better than I do his admirable labours on the development of trilobites, and his most important work on his Lower or Primordial Zone. I enclose an old note of Lyell's to show what he thinks. With respect to Dana, whom I also proposed, you know well his merits. I can speak most highly of his classificatory work on crustacea and his Geographical Distribution. His Volcanic Geology is admirable, and he has done much good work on coral reefs.

If you attend, do not answer this; but if you cannot be at the Council, please inform me, and I suppose I must, if I can, attend.

Thank you for your abstract of your lecture at the Royal Institution, which interested me much, and rather grieved me, for I had hoped things had been in a slight degree otherwise. (40/1. "On certain Zoological Arguments commonly adduced in favour of the hypothesis of the Progressive Development of Animal Life," Discourse, Friday, April 20, 1855: "Proceedings R.I." (1855). Published also in "Huxley's Scientific Memoirs." The lecturer dwelt chiefly on the argument of Agassiz, which he summarises as follows: "Homocercal fishes have in their embryonic state heterocercal tails; therefore heterocercality is, so far, a mark of an embryonic state as compared with homocercality, and the earlier heterocercal fish are embryonic as compared with the later homocercal." He shows that facts do not support this view, and concludes generally "that there is no real parallel between the successive forms assumed in the development of the life of the individual at present and those which have appeared at different epochs in the past.") I heard some time ago that before long I might congratulate you on becoming a married man. (40/2. Mr. Huxley was married July 21st, 1855.) From my own experience of some fifteen years, I am very sure that there is nothing in this wide world which more deserves congratulation, and most sincerely and heartily do I congratulate you, and wish you many years of as much happiness as this world can afford.


(41/1. The following letter illustrates Darwin's work on aberrant genera. In the "Origin," Edition I., page 429, he wrote: "The more aberrant any form is, the greater must be the number of connecting forms which, on my theory, have been exterminated and utterly lost. And we have some evidence of aberrant forms having suffered severely from extinction, for they are generally represented by extremely few species; and such species as do occur are generally very distinct from each other, which again implies extinction.")

Down, November 15th [1855?].

In Schoenherr's Catalogue of Curculionidae (41/2. "Genera et Species Curculionidum." (C.J. Schoenherr: Paris, 1833-38.)), the 6,717 species are on an average 10.17 to a genus. Waterhouse (who knows the group well, and who has published on fewness of species in aberrant genera) has given me a list of 62 aberrant genera, and these have on an average 7.6 species; and if one single genus be removed (and which I cannot yet believe ought to be considered aberrant), then the 61 aberrant genera would have only 4.91 species on an average. I tested these results in another way. I found in Schoenherr 9 families, including only 11 genera, and these genera (9 of which were in Waterhouse's list) I found included only 3.36 species on an average.

This last result led me to Lindley's "Vegetable Kingdom," in which I found (excluding thallogens and acrogens) that the genera include each 10.46 species (how near by chance to the Curculionidae), and I find 21 orders including single genera, and these 21 genera have on average 7.95 species; but if Lindley is right that Erythroxylon (with its 75 species) ought to be amongst the Malpighiads, then the average would be only 4.6 per genus.

Charles Darwin

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