The Rafflesia arnoldii, a parasitic flower found in Sumatra and Borneo, is known for its exceptionally large size and strong odour. It was first described in this 1821 preprint by Robert Brown, who had read his paper on the Rafflesia genus a year before to the Linnean Society of London. It is named in honour of both Sir Stamford Raffles and the botanist Joseph Arnold, both of whom came across the flower in an expedition in Sumatra in 1818.