Bryophytes are the oldest land plants on earth, and have been around for 400 million years or more. Although small, they can be very conspicuous growing as extensive mats in woodland, as cushions on walls, rocks and tree trunks, and as pioneer colonists of disturbed habitats.

They comprise three main taxonomic groups: mosses (Bryophyta), liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) which have evolved quite separately. Worldwide there are possibly 10,000 species of mosses, 7000 liverworts and 200 hornworts.

RBGE's globally important collection of bryophytes has a world-wide coverage. It is particularly rich in historical material collected in Scotland, which contains many types. The collection has grown extensively in the last 25 years with the accquisition of several herbaria.