aces of the gills. This little
experiment will be instructive in two or three points. It will
illustrate the facility with which the spores are disseminated, the
immense number in which they are produced, and the adaptability of the
gill structure to the economy of space, and the development of the
largest number of basidiospores from a given surface. The tubes or
pores in _Polyporei_, the spines in _Hydnei_, are modifications of the
same principles, producing a like result.

In the _Gasteromycetes_ the spores are produced in many cases, probably
in most, if not all, at the tips of sporophores; but the hymenium,
instead of being exposed, as in the _Hymenomycetes_, is enclosed within
an outer peridium or sac, which is sometimes double. The majority of
these spores are globose in form, some of them extremely minute,
variously coloured, often dark, nearly black, and either externally
smooth or echinulate. In some genera, as _Enerthenema_, _Badhamia_,
&c., a definite number of spores are at first enclosed in delicate
cysts, but these are exceptions to the general rule: this also is the
case in at least one species of _Hymenogaster_. As the spores approach
maturity, it may be observed in such genera as _Stemonitis_, _Arcyria_,
_Diachea_, _Dictydium_, _Cribraria_, _Trichia_, &c., that they are
accompanied by a sort of reticulated skeleton of threads, which
remain permanent, and served in earlier stages, doubtless, as
supports for the spores; being, in fact, the skeleton of the hymenium.
It has been suggested that the spiral character of the threads in
_Trichia_ calls to mind the elaters in the _Hepaticae_, and like them
may, by elasticity, aid in the dispersion of the spores. There is
nothing known, however, which will warrant this view. When the spores
are mature, the peridium ruptures either by an external orifice, as
in _Geaster_, _Lycoperdon_, &c., or by an irregular opening, and the
light, minute, delicate, spores are disseminated by the slightest
breath of air. Specimens of _Geaster_ and _Bovista_ are easily
separated from the spot on which they grew; when rolling from place
to place, the spores are deposited over a large surface. In the
_Phalloidei_ the spores are involved in a slimy mucus which would
prevent their diffusion in such a manner. This gelatinous substance has
nevertheless a peculiar attraction for insects, and it is not altogether
romantic to believe that in sucking up the fetid slime, they also
imbibe th