Charles M. Hoy  Charles McCauley Hoy (1897–1923) was a field naturalist who obtained series of mammal and bird specimens for United States National Museum, travelling on expeditions to Australia, China and elsewhere. The large collections of specimens and notes he made in Australia from 1919 to 1922 followed a period of dramatic decline in its mammalian fauna, and have been examined by later workers in efforts to determine the causes of the event. Born in China to foreign missionaries, Hoy returned there in 1922 with a commission from W. L. Abbott to continue collecting specimens for the institution. His successful collecting in that region included becoming the first occidental researcher to obtain a species of rare river dolphin, but his works were curtailed by complications arising from childhood illness – while convalescing from a self-inflicted gunshot injury – and he died there in 1923. Charles M. Hoy was the son of Christian missionaries from the United States of America, active in Japan and China. Hoy was instructed in the techniques of zoological field work during several months at the Smithsonian Institution, and was then directed by W. L. Abbott to undertake a collecting expedition to Australia. He assembled extensive collections and notes on Australian fauna, mostly birds and mammals, obtained at widely separated locations around the continent. The information and material he obtained on his excursions from 1919 to 1922 provides valuable details in the aftermath of what is regarded as extraordinary decline in mammalian fauna in the late nineteenth and early twentieth century. The season and locations of Hoy's field work have been determined in his excursions to New South Wales during 1919, South Australia from 1919 to early 1920, another journey through the south and north of Western Australia during 1920 and continuing to the Northern Territory later that year. In 1921 he travelled out from Sydney to Tasmania then Queensland and is noted as back at that city in April of the next year, preparing for his return journey to the United States. Charles Hoy's Australian ventures assembled small collections of marine animals and reptile and amphibian species, but the greater part his work was in amassing a collection of around one thousand specimens of birds and a similar number of mammals. The final number of mammalian species totalled around one hundred, collected at fourteen locations around the continent. While in Australia he regularly provided reports to the museum curator Garrett S. Miller and was accompanied by local researchers such as Ellis Le Geyt Troughton. Most of the visits to regions were undertaken by sea voyages, with short excursions to local areas near the ports. When Hoy was in Western Australia, his failure to find species at Perth, previously noted as common around the Swan River settlement by John Gilbert and others, saw him directed to the Busselton and Margaret River area.