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THODAY , DAVID ( 1883 - 1964 ), botanist, university professor ;

b. 5 May 1883 at Honiton , Devon , the eldest of the six children of David Thoday , schoolmaster , and Susan Elizabeth (née Bingham ) his wife. The family moved to London where he attended Tottenham grammar school , 1894-98 , before entering Trinity College , Cambridge in 1902 . He specialised in botany under the direction of H. Marshall Ward , A.C. Seward and F.F. Blackman , gaining first class in both parts of the Tripos in 1905 and 1906 , and he won the Walsingham Medal in 1908 . After serving as university demonstrator in botany at Cambridge for two years ( 1909-11 ) he was appointed a lecturer in Physiological Botany in Manchester University in 1911 and became Harry Bolas Professor of Botany in Cape Town University , South Africa in 1918 . In 1923 he succeeded Reginald W. Phillips as Professor of Botany at the University College of North Wales , Bangor , where he remained until he reached the age of retirement in 1949 . After retiring he became Professor of Plant Physiology at the University of Alexandria , Egypt , but returned to Bangor in 1955 .

He obtained a Sc.D. degree at Cambridge , was elected F.R.S. in 1942 and received an hon. D.Sc. of the University of Wales in 1960 . He published Botany: a textbook for senior students ( 1915 : 5 editions) and many important articles in his field, including a series on succulent plants, Kleinia articulata , particularly on their acidic metabolism. His presidential lecture to the British Association, Section K , in 1939 , on ‘ The interpretation of plant structures ’ was seminal.

He was assisted in much of his work by his wife whom he m. 15 June 1910 , and who, as Mary Gladys Sykes of Girton College and a research fellow of Newnham College , was author of a number of papers on botanical subjects . She was the daughter of John Thorley Sykes of Rossett, Denbs. They had four sons. His wife d. in 1943 , and he d. at Llanfairfechan 30 Mar. 1964 .


  • Biographical Memoirs of Fellows of the Royal Society , xi ( 1965 ), 177-83;
  • see ibid. , 184-5 for a bibliography of his scientific papers, 1905-63 ;
  • The Times , 1 Apr. 1964 .


Evan David Jones, F.S.A., (1903-87), Aberystwyth

Published date: 2001