Tropical plants, 19th-century artwork. From left to right, these are: a calabash tree (Crescentia sp.); a betel nut palm (Areca catechu); a cycad (Zamia elliptica); a white fig tree (Ficus virens); and a tamarind tree (Tamarindus indica). Z. elliptica has since been renamed Encephalartos caffer. Across top are the edible fruits of the calabash, fig and tamarind. Artwork from 'Encyclopaedia Metropolitana', an encyclopedia published in London between 1817 and 1845. Thirty volumes were issued in 59 parts, with 22,426 pages and 565 plates.