Dr Watson's lucid introduction to British Mosses and Liverworts, first published in 1955, has since become a standard work. The author gives full descriptions and ecological details of over 200 of the commoner or more notable species, illustrating each to show its diagnostic microscopic and macroscopic features, and also provides brief notes on many other species. The introduction on the general characteristics of bryophytes, and the simple terminology (technical terms are kept to a minimum and defined in a glossary) enable a beginner to use the book without difficulty; the keys and habitat lists will be invaluable to beginners and specialists alike. This third edition incorporates a further 26 species and has brought the taxonomy and nomenclature into line with contemporary practice.