Jean Marie Delavay was a French missionary and botanist who explored China, where he made significant botanical collections in the late 19th century.
Delavay's first posting with the Missions Etrangères de Paris was to Huizhou, east of Guangzhou. Curious about his surroundings, he made excursions within the province and further afield, venturing as far as north-west Yunnan.
While in France in 1881, on a break from his duties, Delavay met the natural history collector and fellow missionary Père Armand David, who had made his final collecting expedition in China in the 1870s. David encouraged Delavay to continue his collecting work and send specimens to the Paris Museum of Natural History. Delavay agreed to the challenge and began this work in Dali, Yunnan Province, in 1882.
Like David before him, Delavay eschewed a large party of assistants and instead went alone, on foot, collecting in Hubei, Sichuan and Yunnan (particularly the Tapintze mountains) over the course of ten years. In this broken landscape of huge ranges and deep valleys, he especially sought out unique alpine species for introduction to western gardens, as well as herbarium specimens for Paris.
Delavay contracted plague in 1888 but recovered (to an extent) and began collecting again. On a holiday to Europe in 1891 he became paralysed in his left arm, but continued collecting plants when he returned to China in 1893, while stationed at Longki. Untiring to the last, in the months before his death in Yunnan in 1895, he managed to amass a further 800 species.
In all, Delavay gathered some 200,000 herbarium specimens. Among these, when examined by Adrien Franchet and others, were found many new genera and over 1,500 new species. Primulas and rhododendrons featured heavily, as well as Magnolia, Philadephus and Osmanthus. Plant names honouring Delavay include Abies delavayi Franch., Magnolia delavayi Franch. and Paeonia delavayi Franch.
Sources:
E.H.M. Cox, 1945, Plant Hunting in China: 115-118
A. Franchet, 1889-1890, Plantae Delavayanae: Plantes de Chine recueillies au Yunnan par l'Abbé Delavay
F.C. Stern, 1944, "The Discoveries of the Great French Missionaries in Central and Western China", Proceedings of the Linnean Society, 156(1): 18.