TEN YEARS' PROGRESS IN LICHENOLOGY. 275
more or less complete, from a large number of localities in the
British Isles, extending from the Shetlands to Essex and Devon-
shire, and from Suffolk to County Mayo in Ireland.
There has been a marked increase in the number of ecological
papers published. The causes for this increase are not far to seek
for they are mainly due to the publication in this country of two
books:—Types of British Vegetation (30), and A Monograph
of British Lichens (31), The former, described in the dedi-
cation as "This first attempt at a scientific description of British
Vegetation," and in the preface as "An endeavour to present
a scientific classification and a balanced picture of British vegeta-
tion, as it exists to-day," gave to investigators a definite plan
by which work could be systematized; the latter became, at
once, the standard of reference for nomenclature and classifica-
tion, and placed that branch of Lichenology on a high level among
Continental works of a similar kind. Part 1 of the "Mono-
graph," originally compiled by the Rev. J. M. Crombie, was re-
arranged and almost entirely re-written by A. Lorrain Smith
(31).
It has not been found practicable to refer to investigations
in strictly chronological order, for it is sometimes advisable
to associate papers that are similar as regards the subject under
investigation without respect to date ; but the order of sequence
has been followed for the most part.
The ecological papers treat of a wide diversity of habitat,
including rocky sea coasts, inland localities, mountain heights
and lowlands. They embrace the rocky coasts of west Ireland,
of Howth Head, and of the Isle of Arran ; the low-lying sand
and shingle of Blakeney Point, Norfolk; the sand-dunes of
Lancashire, the Isle of Man, Devonshire and Somersetshire.
They recall the fresh invigorating sea breeze, the salt splash of
the waves of the incoming tide, the pure atmosphere and the
intense light of the mountain summit.
The lichens in various localities around the coast of the
British Isles have been, during the period under review, investi-
gated ecologically, and important additions have been made to
our knowledge of maritime and marine formations and
associations.
It is to be regretted that the methods of recording results
have not been uniform. It is worth consideration whether