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Abstract

Hepatics. The second class into which the Bryophyta are divided
is a purely natural one. There are no intermediate forms
through which the two groups are connected, though their
close relationship is very apparent. There is always a
natural distinction, requiring no arbitrary line to separate
them.
The gametophyte is varied in structure ; many have
the form of a flat, green plate, while the greater number
develop leaves; yet when leaves are present these have a
distinction of insertion and structure quite different from
those of Mosses. Leaves are always placed in two or three
rows, two lateral and one ventral, the latter row occasionally
being absent. They are usually of delicate consistence,
never have a midrib, and are often divided. Most
Hepatics live only under permanently moist conditions,
but some few can survive even the drying conditions of bare
rock at a high elevation.
The characteristic feature of Hepatics is that while
they have the typical antheridia, archegonia and permanently
attached sporophyte of the class, the sporophyte has
attained a much further reduction than amongst Mosses.
It is no longer a hard-tissued, persistent being, but is reduced
to a comparatively evanescent organ. In most it is
a simple globular or oblong dark capsule, which splits into
four valves at maturity, borne on a long or short pellucid
stalk. In Marchantia and its allies the stalk is almost
absent. In Riccia. reduction has reached its limit, and the
sporophyte is reduced to a spherical spore sack, buried in
the substance of its parent. One order of Hepatics, of
which Anthoceros is the type, has a sporophyte of less reduced
character than the rest, but still of a form not to
be confused with that of a true moss; the shape is long
and slender, and it splits from top to base into two valves.
It is green, and still bears efficient stomata on its surface.
Hepatics may be sorted into three perfectly natural
Orders :—
Marchantiales,
Jungermanniales,
Anthocerotales.
This article describes the genera, including locations they are found. An index of genera is given at the end.

Item Type:	Article
Authors/Creators:	Rodway, Leonard
Keywords:	Royal Society of Tasmania, Van Diemens Land, VDL, Hobart Town, natural sciences, proceedings, records
Journal or Publication Title:	Papers & Proceedings of the Royal Society of Tasmania
Collections:	Royal Society Collection > Papers & Proceedings of the Royal Society of Tasmania
Additional Information:	In 1843 the Horticultural and Botanical Society of Van Diemen's Land was founded and became the Royal Society of Van Diemen's Land for Horticulture, Botany, and the Advancement of Science in 1844. In 1855 its name changed to Royal Society of Tasmania for Horticulture, Botany, and the Advancement of Science. In 1911 the name was shortened to Royal Society of Tasmania.
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