Medical doctor who spent nearly 50 years on the island of Dominica, where he was Principal Medical Officer from 1904 until his death. Following in the footsteps of John Imray, also a doctor on Dominica, Nicholls collected plants in the West Indies and corresponded regularly with Kew on matters of economic botany. Nicholls was born in London and studied medicine in Aberdeen and London. He arrived in Dominica in 1873 as an assistant to Imray and married a Dominican woman, Marion Crompton, in 1877. Continuing Imray's work on building up the island's health service, he also devoted time to agricultural enterprise. In 1892 he published a textbook of tropical agriculture and often sent seeds and plant material to Kew, suggesting their potential for introduction as crops elsewhere. He also sent live plants to Kew in Wardian cases, and was a keen supporter of the Dominica Botanic Garden. A one-time magistrate on the island, he was an active figure in Dominican politics and promoter of its natural history assets. In 1880 Nicholls guided the future British King George V and his brother, Prince Albert Victor, to the summit of Morne Diablotin. He was a Fellow of the Linnean Society and was knighted in the 1920s.

Sources:
Anon., 1926, Kew Bulletin of Miscellaneous Information, 4: 192
L. Honeychurch, A to Z of Dominica Heritage, Dominica Export Import Agency:
http://dominica.dexia.dm/index.php?action=artikel&cat=9&id=150&artlang=en.