Synopsis top ↑
The greatest outstanding need is for a synthesis that attempts to critically define families and, in particular, genera and subgenera. For more than a century nobody has attempted such a synthesis.
This work attempts to answer this need by providing a modern synthesis of what we have learned, mostly in the second half of the twentieth century, about the families and genera of liverworts. It deals primarily with the conceptual bases that underlie a modern classification of the Hepaticae: the boundaries of suborders, families and genera are drawn by evaluating modern criteria. In such an evaluation emphasis is on features largely unused prior to 1950: ramification patterns and branch origins; capsule wall anatomy; seta and stem anatomy; oil-bodies and cell wall criteria.
211 figures, drawn by the author, illustrate these features and also show many
taxa in drawings illustrating basic aspects of each genus. Almost all larger
groups were studied from living plants and emphasis is on liverworts as living
organisms.
The larger genera of Hepaticae are each illustrated with several plates and
emphasis is on "key" genera which occupy critical phylogenetic positions, such
as Lepidozia, Pseudocephalozia and Paracromastigum. No attempt is made at
species diagnoses but generic boundaries, in larger genera, are defined by
illustrating several species per genus. Except for genera with numerous
species, keys to species are provided. In numbered
annotations diverse problems, such as generic relationships and boundaries,
are discussed; key species are often treated at length. As noted in the
Introduction, since all taxa cannot be illustrated and/or described, for all
larger genera the "type" method is used: boundaries are established by
treating (and illustrating) key taxa so as to draw logical boundaries for each
genus -- and family.
The author has conducted field work in the Antipodes for over 40 years,
starting in Fuegia in 1960. He has not only become familiar with all the chief
groups as living plants, but has studied them microscopically in areas as
diverse as Fiji, the Prince Edward Islands., Campbell I., Chile and New
Zealand, residing for months or sometimes years in these regions. The
opportunity to study hepatics in the field has given him a unique opportunity
to learn these organisms as living entities; to drawt cytological details from
living plants, and to place critical material into FAA for subsequent
illustration, especially of the ephemeral sporophytes. Unlike most extant
taxonamic works, which are based on herbarium study, this work tries to give
the reader a "feeling" for the many taxa as living organisms.