The Genus Paeonia - Google Books

https://books.google.de/books?id=mDLASKInbjgC&pg=PA196#v=onepage

Twenty-five species of the genus Paeonia are documented in these pages, including 40 subspecies and varieties. Also included herein is the closely related genus Glaucidium. With only two species, it will be of intense interest to peony fanciers. Waddick…