tions only the vegetative system is probably
developed, and that imperfectly, yet some have ventured to give
names to isolated cells, or strings of cells, or threads of
mycelium, which really in themselves possess none of the elements
of correct classification--the vegetative system, even, being
imperfect, and consequently the reproductive is absent. As already
observed, no fungus is perfect without fruit of some kind, and the
peculiarities of structure and development of fruit form one of the
most important elements in classification. To attempt, therefore, to
give names to such imperfect fragments of undeveloped plants is
almost as absurd as to name a flowering plant from a stray
fragment of a root-fibril accidentally cast out of the ground--nay,
even worse, for identification would probably be easier. It is well to
protest at all times against attempts to push science to the verge
of absurdity; and such must be the verdict upon endeavours to
determine positively such incomplete organisms as floating cells,
or hyaline threads which may belong to any one of fifty species of
moulds, or after all to an alga. This leads us to remark, in
passing, that there are forms and conditions under which fungi may
be found when, fructification being absent--that is, the vegetative
system alone developed--they approximate so closely to algae that it
is almost impossible to say to which group the organisms belong.

Finally, it is a great characteristic of fungi in general that they
are very rapid in growth, and rapid in decay. In a night a puffball
will grow prodigiously, and in the same short period a mass of paste
may be covered with mould. In a few hours a gelatinous mass of
_Reticularia_ will pass into a bladder of dust, or a _Coprinus_ will
be dripping into decay. Remembering this, mycophagists will take note
that a fleshy fungus which may be good eating at noon may undergo such
changes in a few hours as to be anything but good eating at night.
Many instances have been recorded of the rapidity of growth in fungi;
it may also be accepted as an axiom that they are, in many instances,
equally as rapid in decay.

The affinity between lichens and fungi has long been recognized to its
full and legitimate extent by lichenologists and mycologists.[I] In
the "Introduction to Cryptogamic Botany," it was proposed to unite
them in one alliance, under the name of _Mycetales_, in the same
manner as the late Dr. Lindley had united allied order