William Frederick Purcell

William Frederick Purcell (18 September 1866 London - 3 October 1919 Cape Town) was an English-born South African arachnologist and zoologist. He is regarded as being the founder of modern araneology in South Africa.

Purcell was awarded a doctorate after studying at a number of German universities. He then took up an appointment as First Assistant at the South African Museum in charge of terrestrial vertebrates. He was the first South African zoologist to start a systematic study of spiders, devising keys and providing full descriptions of species. Up to that time Arthur Stanley Hirst (1883–1930), Pickard-Cambridge and R. I. Pocock of the British Museum had occasionally named spiders sent them from South African sources. Pocock especially was supplied with unknown specimens from Natal and Rhodesia, many coming from Selmar Schonland, the botany professor at Rhodes University.

South Africa is a fertile hunting ground for the study of Mygalomorphae or 4-lunged spiders, and both Purcell and R. W. E. Tucker who succeeded him, were drawn to this group, as was J. Hewitt. William and Anna Purcell afford an example of collaboration in arachnology of husband and wife, the other well-known couple being George and Elizabeth Peckham from the States who worked on South African Salticidae.

A species of South African gecko, pachydactylus purcelli, is named in his honor.