Darwin book worth up to $100,000 found on shelf

A detail of British artist John Collier's 1883 painting of Charles Darwin is displayed as part of an exhibition in Darwin's former home, Down House, in Kent, southern England February 12, 2009.

LONDON (Reuters) - A first edition of Charles Darwin's "On the Origin of Species," which had been kept in a toilet bookcase for years, will go on sale this week and is expected to fetch 40-60,000 pounds ($66-100,000).

Christie's auctioneer will offer the book on Tuesday, the 150th anniversary of its original publication.

The copy was bought by the family of the current owners for "a few shillings" in the late 1960s or early 1970s, the auctioneer said.

They only recognized that they owned such a valuable edition when they recognized a picture of the spine of another first edition of the work at a Darwin exhibition.

(Reporting by Mike Collett-White, editing by Paul Casciato)