Miss Mary Gladys Sykes, British botanist, was the daughter of John Thorley Sykes, a cotton broker, and his wife Mary Louisa Marks. She was educated at home and continued her studies at Queen's College, Chester, and from 1902 at Girton College, University of Cambridge. Although she obtained a first class
pass in both parts of the Natural Science Tripos at Cambridge she was not awarded a degree, as the university's policy at this time was not to award degrees to women. She started her research career as a research fellow of Newnham College, Cambridge, but also did some teaching. Her early research was mainly in cytology and histology. However, she was a versatile botanist and subsequently became interested in the anatomy and morphology of vascular cryptogams.
In June 1910 she married David Thoday*. By that time she had published some 20 scientific papers under her
maiden name, including 'The anatomy and morphology of Tmesipteris' [a genus of club mosses] (Annals of Botany, 1908), 'Notes on the nuclei of some unisexual
plants' (Ibid, 1909), and 'The
anatomy and morphology of the leaves and inflorescences of Welwitschia mirabilis' (Philosophical
Transactions of the Royal Society of London, 1911). From sometime before her marriage she collaborated
with David Thoday in research on plant physiology. For example, they published 'Preliminary
observations on the transpiration current in submerged water plants' in the Annals of Botany in 1909. In 1911 they
moved to Manchester, where Mrs Thoday became an honorary research fellow in the
University of Manchester. In March 1919 they arrived in South Africa for a stay
of almost four years. During this period she published a paper on 'Ripening of
seed in Gnetum gnenom and Gnetum africanum' in the South African Journal of Science (1920,
Vol. 17, pp. 189-191).
The Thodays left South Africa for Bangor, Wales, where Mrs
Thoday became an honorary lecturer in botany in the University College of North
Wales. She was active in the women's suffrage movement, also during her stay in
South Africa. All four her sons were on active duty during World War II
(1939-1945), three of them in the Royal Air Force and one as a radio officer in
the Merchant Navy. She died in 1943 after a long illness.
