8vo. Errata slip; one diagram, numerous tables. (Spotting to title and a few other leaves.) Original green cloth, covers with blind frame, spine gilt (hinges starting, some light rubbing and wear).

FIRST EDITION of this sequel to Darwin's Fertilisation of Orchids, based on painstaking experiments he had undertaken since 1866, making the work his most ambitious plant book to date. "It was too technical and too detailed to command a wide sale," although 1500 copies were sold before the end of 1876. Freeman 1249.