“…The EP contains high levels of glycerylphosphorylcholine (GPC) (Dawson, Mann & White, 1957;Mann, 1959) and a considerable proportion of the nitrogenous material was soluble in ethanol (Mann, 1959). The major constituents of the VS are citrate (Humphrey & Mann, 1949), ergothioneine (Leone & Mann, 1951;Mann & Leone, 1953), inositol (Mann, 1951(Mann, , 1954 and protein (Mann, 1959;Boursnell, Baronos, Briggs & Butler, 1972). Boursnell & Coombs (1966) reported the presence of a powerful haemagglutinin in boar VS, later identified as a mixture of proteins ('protein H') of high isoelectric point by Nelson & Boursnell (1966), Boursnell & Briggs (1969) and Lavon, Briggs & Boursnell (1973).…”