DARWIN, Charles (1809-1882). Naturalist.
Important Autograph Letter Signed to the Revd F Howlett, 3 pages 8vo with envelope front adhering to the back, Down, Beckenham, Kent, 21 September [1878]. Affirming his evolutionary beliefs in relation to camels and ostriches, admitting that Hewlett's 'problem' is indeed a perplexing one, made more so by the lack of understanding of the histology of the blood corpuscles.

'... I shd doubt almost the peculiar shape of the corpuscles in the Camelidae being due to inheritance from a remote progenitor; & most of the points which you specify as being alike in camels & ostriches could be accounted for, as it appears to me, more probably by adaptation to similar conditions, rather than to inheritance from a common ancestor, extremely remote in time. ...'

This is, of course, a statement of the central thesis of Darwin's revolutionary beliefs, and treats in a plainly matter-of-fact way the possibility of similarities between the species being due either to common ancestry or to adaptation to circumstances. Unpublished, not in Burkhardt and Smith's Calendar of the Correspondence where no other letters to or from this correspondent are listed.
[No: 7945]