He was the author of several books devoted either to succulents or to cacti.
Published in 1915, this is an interesting contribution with 48 B&W pictures
Right: Agave latissima (Extracted from the pdf of the link above)
Published in 1905, In the Annual Report of the Missouri Botanical Garden. He proposed to split the Cereus genus of Schumann as defined 5 years before into several subgenera that were then recognized (or resurected) as genera By Britton and Rose 15 years later.
Right: Alwin Berger. Kakteen von A bis Z, Walther Haage, Neumann, 1983.
No copyright (public domain)
Published in 1929, this is an exhaustive contribution (334 pages, 104 B&W pictures) of an unsufficiently known author who had a broad scientific. knowledge
Right: Ariocarpus trigonus (p. 333)
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