222 SIXTY YEARS OF BRITISH MYCOLOGY.
early stage in the life history of both. Again Tubercularia as
the conidia of Nectria, Isaria as those of Cordyceps. Many species
of Oidium as a condition of Erysephe, and so on, so that at the
same time that true species have been increased, spurious
species have been eliminated.
There still remains behind a great number of genera, which
are retained provisionally as Incomplete Fungi, the life-history of
which still remain for future investigation. Some of these are
"Moulds" and others belong to the Sphaeropsideae. Amongst
the latter are a large number of "pests" or parasites on living
plants, many of them being very destructive. With some
persons it is an open question whether the Myxomycetes are
fungi, or intermediate organisms between fungi and the lower
animals ; generally, however, they are accepted as a unique and
peculiar group of fungi, or at the least more closely allied to
fungi than to anything else. Sixty years ago as many of them
as were then known were classed with the "Puff Balls" or
Gastromycetes.
Accepting then the conclusion that British Mycology has
advanced considerably during the past sixty years, not only in
a great numerical increase of species, but also in an increased
knowledge of their structure and relationship, we are led to
enquire finally what has been the principal agent which has
produced this result? To this question there can be but one
answer, viz.: The improved microscope and the great accession
of microscopical observers. There is no group of Fungi in
which the microscope has not been employed ; even the
Hymenomycetes, such as the Agarics, for instance have had to
submit to investigation. Perhaps amongst these plants
microscopical distinctions have been pushed to their extreme
limit. It seems to be "sharp practice" to separate two Agarics,
so closely resembling each other as to be indistinguishable by
the naked eye, simply because one of them has spores which are
two or three micro-millimetres larger or smaller than the other.
One of the greatest sinners in this respect has been Britzelmeyr,
the Bavarian mycologist.
We must bear in mind that the Royal Microscopical
Society was inaugurated in 1840, and that the Quekett Micro-
scopical Club dated a quarter of a century after, hence all their
work and influence falls well within the past sixty years. The
full meaning of these facts will be appreciated by Microscopists,