TILLYARD, ROBERT JOHN (1881-1937), his first name is sometimes given as Robin, entomologist and geologist,

was the son of J. J. Tillyard and was born at Norwich on 31 January 1881. He was educated at Dover College and intended to enter the army but was rejected on account of having suffered from rheumatism. He won a scholarship for classics at Oxford and another for mathematics at Cambridge, and decided to go to Queen's College, Cambridge. He graduated senior optime in 1903. He went to Australia in 1904 and was appointed second mathematics and science master at Sydney Grammar School. Nine years later he resigned and did a research degree in biology at Sydney university and took his research B.Sc. degree in 1914. He was seriously injured in a railway accident in this year and had a slow recovery, but in 1915 became Linnean Macleay Fellow in Zoology at the university of Sydney. He was appointed lecturer in Zoology in 1917. In the same year he published in the Cambridge Zoological series, The Biology of Dragonflies, and he also received the Crisp prize and medal of the Linnean Society of London. In 1920 he was appointed chief of the department of biology at the Cawthron Institute, Nelson, New Zealand. In the same year the honorary degree of D.Sc. was conferred on him by Cambridge university.

Tillyard did good work in New Zealand and established a reputation for his work on the biological control of plant and insect pests. He is popularly best known for his introduction of a small wasp as an agent for controlling woolly aphis in apple-trees. In 1925 he was elected a fellow of the Royal Society, London, and in the following year he published his book on The Insects of Australia and New Zealand, a comprehensive work with many illustrations. In this year he was awarded the Trueman Wood medal of the Royal Society of Arts and Science, London, and was appointed assistant-director of the Cawthron Institute. He returned to Australia in 1928 to become chief Commonwealth entomologist under the Council for Scientific and Industrial Research. He held this position for six years, but the state of his health compelled him to retire on a pension in 1934. While he was holding this position he was awarded the R. M. Johnston memorial medal of the Royal Society of Tasmania in 1929 and the Clarke memorial medal of the Royal Society of New South Wales in 1931. In 1935 he was given the von Mueller medal. His health improved after his retirement and he busily continued his scientific studies. He was well known in the United States which he had visited more than once. He died following a motor accident on 13 January 1937. He married in 1909 Patricia Cruske who survived him with four daughters. In his last years Tillyard was much interested in some work on supposed pre-Cambrian fossils in South Australia which was done in co operation with Edgeworth David (q.v.). The account of their investigations is contained in Memoir on Fossils of the late Pre-Cambrian, by David and Tillyard, published in 1936.

Tillyard had great enthusiasm and powers of work and was one of the most active-minded of men. He did important work in Australian palaeontology in his studies of Permian and Triassic insects, and was a foremost authority on fossil insects generally. His predominant interest, however, lay in the evolution of different types of insects and their biological control. As an entomologist he had a world-wide reputation. His published papers must have approached 200. Some of them were appearing in America in the last year of his life. He was also much interested in psychical phenomena, and attempted to apply scientific methods to their investigation.