If you are looking for older information on Begonias, there are some fascinating historical resources online. There are also more random jewels of the internet included.
Begonia Research Links:
Brazil – Species listing
Cornell U – Herbarium Images
E flora of India – Begonia species list & images
French Begonia Images
Genome size variation in Begonia
Google search – Begonia ‘Graf Johann Harrach’
Hellberg photos – Begonia stomates
Japan – Pompoco village
Japan – Matsue Vogel Park
Peter Moonlight Twitter
Pollination rings for hybridizing
Systematics of begonias
UK – John Jerrard – Begonia Collection
Wikiwand Begonia Species List
Begonia Database
Plant List
Jardin Exotique Begonia Collection
Claude Alain, France
Coleccionista de Begonias – Mexico
Begonia History Links:
KOLZ Begonia Research Center
http://www.plantillustrations.org
Search Results – Biodiversity Heritage Library
Digitized Historic Garden Literature :
American Horticultural Society
Links – Flora Malesiana
Botanical names to Common names
HathiTrust Digital Library
Gallica Search
Biographies of American Nurserymen
Library Genesis
A Five Year Plan for Geraniums
Library.fes.de
European Nursery Catalogue Collection :
Rochefort Begonia Collection
Digital Historic Plant Catalogues
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