for the present the consideration of this influence, I shall
simply indicate some of the peculiar situations in which Fungi
arc occasionally found.
Amongst the higher Fungi, the Coprini. (Plate 12, fig. 1),
and those species oî Agaricus, as for example A. disseminatus,
which are most nearly allied to them, are most capricious in
their habitats. Old damp carpets, naked walls, pestilential
drains entirely concealed from sight, and other anomalous
situations, are amongst those in which they assume an occasional
habitat, their proper place for the most part being-
decayed wood, or the dung of graminivorous animals, which
closely resembles it in the Fungi which it nourishes. As the
Coprini are amongst the most rapid in their growth of any
Fungi, as every one knows who has watched their progress in
a new hot-bed, they sometimes appear in the most unexpected
situations. I t is, for instance, not very uncommon to find
them on the dressings of amputated limbs, and surgeons are
in consequence sometimes very unjustly charged with negligence
by persons who are not acquainted with the speed with
which a Coprinus may pass through every stage of growth
from the spore to the perfect pileus. Where these plants—
as, for example, Coprinus radiatus and Agaricus disseminatus
—are developed on bare walls, they throw out an enormous
quantity of mycelium, in order to avail themselves as much as
possible of the moisture of the surrounding air.
Though Fungi cannot exist without a certain degree of
moisture, they suffer in general from its excess. A few species,
however, are never found except on substances immersed
in water. The beautiful scarlet Mitrula paludosa, which is
the ornament in summer of every little quiescent drain in
some parts of Wales, uniformly grows on leaves or other
decayed vegetable matter floating in water, while Vihrissea
truncorum, so remarkable for shooting out its long threadlike
sporidia under the influence of the sun, is found on immersed
logs or sticks. A fine Sphæria, not yet observed in
this country, is found in Algiers on submarine phænogams,
and other instances occur where the daily wash of salt-water
has not prevented the growth of Fungi. The ubiquitous
Sphæria herharum flourishes even on seaweed thrown up by
the waves.
I am not at liberty to reckon as Fungi the curious Moulds
w'hioh grow on dead fish, making them conspicuous as they
float on the surface of the water by the foggy halo which surrounds
them. These productions differ so essentially in their
mode of reproduction from Fungi in general, that at present
it would he rash to speak too positively about them ; but, inasmuch
as their peculiar characters seem to depend entirely
upon the degree of moisture to which they are exposed, there
is some reason to hesitate and to wait for further information.
I have no doubt that the Mould which is so common on flies
in autumn, oozing out as it were between their abdominal
rings, is a mere condition of one of these anomalous productions.
Nay, it was known long since that the same animal
which, when immersed in water, produced one of these
puzzling plants, when exposed to a slight degree of moisture
gave birth to a true Mucor, or Mould.
A gigantic Mould, of a dark shining green when dry, appears
frequently on casks, or on the walls in oil-mills. The
same species occurs sometimes in great abundance on casks
of grease, flourishing in the most wonderful degree, and ultimately
exhausting to a great depth the substance in which it
grows. As it is far larger than any of the common species
of Mucor which grow on fruit or decaying vegetables, it was
long considered as belonging to a distinct genus, under the