From The Cactaceae Vol. 2 by Britton and Rose by way of  the Catalog of Botanical Illustrations, Department of Botany, Smithsonian Institution

Plate Number: 1767

Cephalocereus barbadensis (Cactaceae) – Type; Collection: , U.S.A., New York Botanical Garden; flowering branch.
Artist: Eaton, Mary Emily – Date unknown – watercolor
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