He was born on 15 October 1857 and joined the Public Service of New Souih Wales on 23 March 1891 and became a Timber Inspector in the Department of Public Works, 1 January 1894. Somewhere about 1904 he left the Public Service and joined the staff of Gibbs Bright Ltd, and around 1908 he established the firm of de Coque and Underwood of Bridge Street. Sydney.
de Coque was a joint collector of Eucalyptus nubila with J. L. Boorman (q.v.) in the Dubbo area of New South Wales, November 1897.For a number of years he was a member of the Royal Society (1899—1910) and a Medallist for the year 1894.
Source: Extracted from: Hall, N. (1978) Botanists of the eucalypts. Commonwealth Scientific and Industrial Research Organisation, Melbourne