Born in Ealing and educated at Pinner County school. Worked at the NHM from 1947 until retirement. He now lives in the Lake District. His special interest was in the Scarabaeidae, especially Catoniinae, and he published three articles on this family: 'A revision of the Australian species of the genus Glycyphana Bumeiaterl, Journal Australian Entomological Society, 13, 1974, 111-128; 'A catalogue of the type specimens of the Cetoniiae described by J.G.Arrow with a complete bibliography of his entomological works', Bull.Br.Mus.nat.Hist., 1974, 25-44; and 'A catalogue of the type specimens of the Scarabaeinae and the smaller Lamellicorn families described by J.G.Arrow, ibid., 37, 1978, 97-113.

He was responsible for the first capture of Atheta strandiella Brundin in Britain (on the Shetlands in 1963) and subsequently published, with Peter Hammond, a note about it and other members of the genus in Ent.mon.Mag. , 107, 1971, 153-57. With the same author he also published 'The Coleopterous fauna of exotic herbivorous and carnivorous mammal dung at Windsor', Ent.Gaz,, 23, 1972, 61-65. His other publications include 'Plant and animal collections' in Land, A.B. (ed.) The Expedition Handbook, 1978, 196-200; 'Colooptera' in Berry, R.,J. and Johnston, J.L., The Natural History of  Shetland, 1980, 306-311; and with Waterston, A.R., Owen, J.A., Welch, R.C., and Hammond, P.M., part 4 'Insecta: Colooptera' in Waterston, A.R., 'Present knowledge of the non-marine invertebrate fauna of the Outer Hebrides', Proceedings Royal Society of Edinburgh, 79, 1981, 215-321.

Bacchus does not have a personal collection. Specimens collected by him may be found in the NHM and in other major museums. (MD 1/22)