Genus Thodaya

For David Thoday (1883–1964), English Cambridge-trained botanist, Harry Bolus professor at the University of Cape Town (1918–1922), professor of botany at the University College of North Wales, now the University of Wales, Bangor (1923–1949). He authored Botany: A Textbook for Senior Students (1915: 5 editions), many scientific papers on succulent and parasitic plants, and a revision of the genus Passerina, etc., but his main interest was on plant physiology – he developed the Thoday potometer (measures the rate of water uptake of a leafy shoot) and Thoday respirometer (measures the rate of respiration of a living organism by measuring its rate of exchange of oxygen and/or carbon dioxide). His presidential lecture to the British Association, in 1939, on ‘The interpretation of plant structures’, was seminal. He was elected a Fellow of the Royal Society in 1942, and received an honorary DSc from the University of Wales in 1960.