20th-century Belgian botanists

Émile Auguste Joseph De Wildeman (19 October 1866, Saint-Josse-ten-Noode – 1947) was a Belgian botanist and phycologist. He is known for his investigations of Congolese flora.
From 1883 to 1887, he studied pharmacy at the Université libre de Bruxelles. In 1891, he began work as a preparateur at the Botanical Garden of Brussels, an institution where he later served as director. In 1892, he received his doctorate in sciences (academic advisor, Leo Errera) and in 1926 attained the title of professor.

Lucien Leon Hauman-Merck (8 July 1880, in Ixelles – 16 September 1965, in Brussels) was a Belgian botanist, who studied and collected plants in South America and Africa.
He received his education in Gembloux, and afterwards relocated to Argentina, where he obtained a position in the department of agronomy and veterinary medicine at the University of Buenos Aires. From 1904 to 1925 he taught classes in botany, plant pathology and agricultural microbiology at the university. In 1910 he laid the foundations for its botanical garden.In Argentina he conducted important phytogeographical research, and he also performed plant collection duties that involved excursions to Paraguay, Chile and Uruguay. In 1927 he returned to Europe, where from 1928 to 1949, he served as a professor of botany at the Free University of Brussels. During this time period, he studied African flora, about which, he collected numerous plants in the Belgian Congo. In 1949 he returned to Argentina as an honorary professor at the University of Buenos Aires. The "Jardín Botánico Lucien Hauman" at the university is named in his honor.The genera Haumania (J.Léonard, 1949) and Haumaniastrum (P.A.Duvign. et Plancke, 1959) commemorate his name, as do species with the epithet of haumanii.

Célestin Alfred Cogniaux (7 April 1841 – 15 April 1916) was a Belgian botanist. Amongst other plants, the genus Neocogniauxia of orchids is named after him.
In 1916 his enormous private herbarium was acquired by the National Botanic Garden of Belgium.