HANDBOOK
OF
BRITISH HEPATICyE.
IN T R O D U C T IO N .
T h e Hepaticae, or Liverworts, have always been
regarded as closely related to the Mosses, and in
olden times were associated with them. In constituting
his alliances Lindley united them in his
Muscal Alliance, and this has since been maintained,
although there is sufficient distinction between
them to be recognized by the naked eye. The
most prominent and popular distinctions are that,
in the Hepaticae the capsule, or spore-bearing
apparatus, splits when mature into four valves ;
whereas in the Mosses the capsule remains entire,
and is closed by a lid, or operculum, which falls
away to permit of the escape of the spores. This
is a general character to which on both sides there
are some exceptions, since some few of the
Hepaticae are devoid of a four-valved capsule, and
amongst Mosses the Andreaceae possess a valvular
capsule. In another aspect, that of vegetation, a
difference is also recognized, in that the Mosses are
foliaceous, possessing a stem and leaves, whereas
the Hepaticae are most commonly foliaceous, but