Edition 1 (1937) of this work listed just over 2000 species. A preliminary survey for this revision showed a three-fold increase of species for inclusion and an overall increase of information available for those in Edition 1. Families are being dealt with alphabetically, and genera within families, and species within genera also alphabetically. Volume 5 herewith contains families S to Z with 800 species, with some additional information relevant to families A to R, and also information regarding cryptogams which has been excluded from the first edition. European and trade-names, if known, are given for each species. There follow a brief description, the sort of habitat each frequents, and then the known economic attributes in West Africa, and over the rest of Africa and beyond, if so wide-spread.