inute species is an absolute necessity
to ensure accurate identification. Little special remark is called for
here, since the methods adopted for other objects will be available.
Specimens which have become dry may be placed in water previous to
examination, a process which will be found essential in such genera as
_Peziza_, _Sphaeria_, etc. For moulds, which must be examined as opaque
objects, if all their beauties and peculiarities are to be made out, a
half-inch objective is recommended, with the nozzle bevelled as much
to a point as possible, so that no light be obstructed.[B]

In examining the sporidia of minute _Pezizae_ and some others, the aid
of some reagent will be found necessary. When the sporidia are very
delicate and hyaline, the septa cannot readily be seen if present; to
aid in the examination, a drop of tincture of iodine will be of
considerable advantage. In many cases sporidia, which are very
indistinct in glycerine, are much more distinct when the fluid is
water.

The following hints to travellers, as regards the collection of fungi,
drawn up some years since by the Rev. M. J. Berkeley, have been widely
circulated, and may be usefully inserted here, though at the risk of
repetition:--

"It is frequently complained that in collections of exotic plants, no
tribe is so much neglected as that of fungi; this arises partly from
the supposed difficulty of preserving good specimens, partly from
their being less generally studied than other vegetable productions.
As, however, in no department of botany, there is a greater
probability of meeting with new forms, and the difficulties, though
confessedly great in one or two genera, are far less than is often
imagined, the following hints are respectfully submitted to such
collectors as may desire to neglect no part of the vegetable kingdom.

"The greater proportion, especially of tropical fungi, are dried,
simply by light pressure, with as much ease as phoenogamous plants;
indeed, a single change of the paper in which they are placed is
generally sufficient, and many, if wrapped up in soft paper when
gathered, and submitted to light pressure, require no further
attention. Such as are of a tough leathery nature, if the paper be
changed a few hours after the specimens have been laid in, preserve
all their characters admirably; and if in the course of a few weeks
there is an opportunity of washing them with a solution of turpentine
and corrosive sublimate, subm