Born in Guernsey and trained as a solicitor. Stayed in Guernsey only intermittently, living at different times in the USA, Paris, Alderney, London, Devon, Hampshire and Cornwall. Awarded a bonze medal by the Royal Cornwall Polytechnic Soc. for an essay on Cornish beetles. Also interested in botany and Hymenoptera. Died at Totnes. A collection of 5000 beetles made by Marquand is in the Guille-Alles Museum, Guernsey, originally in a 12 drawer cabinet and 20 store boxes, together with mss (4 pages). The collection may have been in the possession of W.A.Luff before his death in 1910.