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Darwin Correspondence Project

From T. H. Huxley   [before 3 October 1857]1

Cuviers definition of the object of Classification seems to me to embody all that is really wanted in Science—it is to throw the facts of structure into the fewest possible general propositions— This of course leaves out of view & passes by, all questions of pedigree & possible modifications—dealing with existing animals and plants as faits accomplis2

I for one believe that a Scientific & logical Zoology & Botany are not at present possible—for they must be based on sound Morphology—a Science which has as yet to be created out of the old Comparative Anatomy—& the new study of Development When the mode of thought & speculation of Oken & Geoffroy S. Hilaire & their servile follower Owen,3 have been replaced by the principle so long ago inculcated by Caspar Wolff & Von Baer & Rathke4 —& so completely ignored in this country & in France up to the last ten years—we shall have in the course of a generation a science of Morphology & then a Scientific Zoology & Botany will flow from it as Corollaries—

Your pedigree business is a part of Physiology—a most important and valuable part—and in itself a matter of profound interest—but to my mind it has no more to do with pure Zoology—than human pedigree has with the Census— Zoological classification is a Census of the animal world

Ever yours faithfully | T. H. Huxley Chas. Darwin Esq

CD annotations

2.2 for they … Morphology] ‘why from morphology’ added ink
Top of first page: ‘Huxley on Classification’ink
Bottom of first page: ‘11’5 brown crayon
First CD note: 6
Huxley says that the cleft & loops of arteries in air-breathing mammals is true, not withstanding Baudement.7 | (Keep this)
Second CD note:
No doubt there is classification on mere aggregate resemblance.— But most [interl] nat. search for something more either tacitly or overtly for [del illeg] plan of creation &c.—& this I believe is genealogical.— Take races of man, suppose them perfectly known, wd not genealogical be most perfect, even if it did separate some few races from their nearest like form.— Generally no doubt resemblance wd go with genealogy.—


Dated by the relationship to the letter to T. H. Huxley, 3 October [1857].
Huxley is responding to CD’s view, as put forward in the letter to T. H. Huxley, 26 September [1857], that classification should be essentially genealogical.
Huxley associated Richard Owen’s methodology with Lorenz Oken’s Naturphilosophie and with the philosophical anatomy of Étienne Geoffroy Saint-Hilaire (see A. Desmond 1982 and di Gregorio 1984).
The study of the developmental history of organisms (Entwicklungsgeschichte) that had begun to flourish in Germany owed its origin to the work in embryology of Caspar Friedrich Wolff, Karl Ernst von Baer, and Martin Heinrich Rathke.
The number of CD’s portfolio of notes on classification.
Associated with this letter in DAR 205.5 are two separate notes in CD’s hand. The first may pertain to the section of the letter that is now missing.
CD refers to the view that at an early stage of development the embryos of mammals possess gill clefts and branchial arteries, somewhat like fish. Émile Baudement had challenged this view in Baudement 1847.


Baudement, Émile. 1847. Observations sur les analogies et les différences des arcs viscéraux de l’embryon dans les deux sousembranchements des vertébrés. Annales des Sciences Naturelle. Zoologie 3d ser. 7: 73–86.

Desmond, Adrian. 1982. Archetypes and ancestors: palaeontology in Victorian London, 1850–1875. London: Blond & Briggs.


On classification and possibilities of a scientific morphology and zoology. CD’s "pedigree business" is important for physiology but has nothing to do with pure zoology any more than human pedigree has to do with the census. Zoological classification is a census of the animal world.

Letter details

Letter no.
Thomas Henry Huxley
Charles Robert Darwin
Sent from
Source of text
DAR 205.5: 218
Physical description
4pp inc †, 2 CD notes

Please cite as

Darwin Correspondence Project, “Letter no. 2144,” accessed on 16 September 2021,

Also published in The Correspondence of Charles Darwin, vol. 6