I found this poem among three books of scientific poetry reviewed in Science Magazine, 2 October 2009. It’s from Darwin: A Life in Poems by Ruth Padel, ISBN 9780701183851. There’s a note at the bottom of the poem – all the quotations are from Darwin himself.
A Pigeon Fancier’s Manual
“This horrid Species thing.” He’s got to write it new –
and smaller! Just (just!) summarizing his views.
“My rag of a book. It cost me so much labour
I almost hate it.” They build a billiard room
beside the study. He pots coloured balls like sweets
as a rest from work. She protects him from visitors
and relatives. No one’s ill – they take a family holiday
on the Isle of Wight. He finishes in April.
The publisher’s reader says, “Make it a manual
on pigeon-breeding! Forget the rest.
Everyone loves pigeons – it’d be reviewed
by every journal in the land.” John Murray knows
a good thing when he sees one, he’ll do a small
edition but it’s still too long. Edit. Vomit. Edit.
Shadows in the dawn. Resist the lure
of ever more evidence. He sends it and disappears
for a water cure. “Severely ill.” In November,
at fifteen shillings, it sells out in one go.