Galton refers to the published report of his experiments on the transfusion of blood between different colours of rabbits (Galton 1871). The experiments were designed to test CD’s hypothesis of pangenesis. See letters from Francis Galton, 9 January 1871, n. 1, and 25 April 1871 and n. 1.

See Nature, 4 May 1871, pp. 5–6. Galton was replying to a criticism that CD had made of his rabbit experiments, namely, that Galton was mistaken in assuming that ‘gemmules’, the material of hereditary transmission postulated by CD, were contained in the blood (see letter to Nature, [before 27 April 1871]). Galton stated that he had been misled by CD’s own terminology in Variation 2: 374 and 379, which described gemmules as ‘circulating’ and ‘diffused’ within the body. He concluded his letter in Nature with the paragraph: I do not much complain of having been sent on a false quest by ambiguous language, for I know how conscientious Mr. Darwin is in all he writes, how difficult it is to put thoughts into accurate speech, and, again, how words have conveyed false impressions in the simplest matters from the earliest times. Nay, even in that idyllic scene in which Mr. Darwin has sketched of the first invention of language, awkward blunders must of necessity have often occurred. I refer to the passage in which he supposes some unusually wise, ape-like animal to have first thought of imitating the growl of a beast of prey so as to indicate to his fellow monkeys the nature of expected danger. For my part, I feel as if I had just been assisting at such a scene. As if, having heard my trusted leader utter a cry, not particularly well articulated, but to my ears more like that of a hyena than any other animal … I had … dashed down a path … followed by the approving nods and kindly grunts of my wise and most-respected chief. And I now feel, after returning from my hard expedition … that the suspected danger was a mistake.... I am given to understand … that my leader’s cry had no reference to a hyena down in the plain, but to a leopard somewhere up in the trees; his throat had been a little out of order—that was all. Well, my labour has not been in vain; it is something to have established the fact that there are no hyenas in the plain, and I think I see my way to a good position for a look out for leopards among the branches of the trees. In the meantime, Vive Pangenesis.