John Gossweiler served as botanist to the Government of Angola from 1899 until his death. His collections of African plants were received steadily by European and American herbaria over the course of his 53 years in Angola.
Gossweiler was born in Regensdorf, Zurich, where he was probably christened Hans, though he always called himself John, or João. He studied horticulture in Zurich, Stuttgart and Dresden, proceeding to spend four years in London at the Royal College of Science, South Kensington, and the Royal Botanic Gardens, Kew. Acquiring a passion for botany from William Thistelton-Dyer at Kew, he was then appointed to work for the government of Angola in the country's new Garden of Acclimatisation at Luanda. Gossweiler remained in Luanda from 1899 until his death.
After arriving in Angola (then in the process of becoming a Portuguese colony), Gossweiler found that the garden was not ready, and instead began to make botanical collections in the coastal area around Luanda and the plateau of Malange. These plants he sent to Portugal. In 1905 he studied the native rubber-producing plants of the Ganguela and Bié Plateau region and collected many novel plants along the River Cubango.
The creation of the Cazengo Colonial Garden, of which Gossweiler was destined to serve as director, was finally underway by 1907. Sited on an abandoned plantation, Gossweiler gathered there living plants from Sri Lanka, Goa, Malaysia and tropical America, as well as native species. His collecting of dried specimens never ceased, meanwhile, and in 1915-1916 he carried out extensive work in Subliali, Pango Munga and the rainforest region of Mayombe, and near the source of the River Zanza, where he was accompanied by his wife.
Gossweiler worked for the private company Fomento Geral de Angola from 1919-1926. He took the opportunity to make significant collections during this time along the southern bank of the Congo, in the Dembos region and at Quiçama.
Re-entering government service in 1927, Gossweiler began the task of establishing an experimental cotton station in Catete, then in 1932 travelled to Amboim to investigate diseases of coffee. Here he made interesting collections in the mist forest south of Cazengo, and afterwards spent a period in Portugal, working on his collections at the University of Coimbra and the Colonial Garden in Lisbon.
Gossweiler would make two further important collecting expeditions in Angola. In 1937-8 he accompanied the Portuguese botanists Luis Carrisso and Francisco Mendonça of Coimbra University, and Arthur Exell of the British Museum, on a lengthy expedition covering some 8,000 miles. During their work, Carrisso unfortunately suffered a fatal heart attack. Work nevertheless progressed, the results contributing to the Conspectus Florae Angolensis (first volume published in 55 parts between 1937 and 1951). His last significant expedition was made in 1947 to the forests of Dundo in the extreme north-east of Angola.
Gossweiler's collections amounted to 14,000 numbers, and were distributed among many of the great herbaria of the world, including that of the British Museum (the Natural History Museum, London). His publications included Carta Fitogeográfica de Angola (co-authored with F.A. Mendonça, 1939) and the Flora Exótica de Angola (1949-1950).
In 1936 the Portguese government recognised Gossweiler's services to Angolan agriculture with the Comenda da Ordem do Imperio Colonial, and in 1950 he was elected a Foreign Member of the Linnean Society of London for his work in systematic botany. He is commemorated in the genera Gossweilera S.Moore and Gossweilerodendron Harms.
Sources:
A.W. Exell, 1952, "John Gossweiler", Taxon, 1(6): 93-94
A. Fernandes, 1954, "John Gossweiler (1873-1952)", Vegetatio, 4(5): 334-335.
