fungi. The old stems of the common nettle, for example, perform the
office of host to about thirty species.[F] Of these about nine are
_Pezizæ_, and there are as many sphæriaceous fungi, whilst three
species of _Dendryphium_, besides other moulds, select this plant.
Some of these have not hitherto been detected growing on any other
stems, such as _Sphæria urticæ_ and _Lophiostoma sex-nucleatum_, to
which we might add _Peziza fusarioides_ and _Dendryphium griseum_.
These do not, however, include the whole of the fungi found on the
nettle, since others are parasitic upon its living green parts. Of
these may be named _Æcidium urticæ_ and _Peronospora urticæ_, as well
as two species described by Desmazières as _Fusisporium urticæ_ and
_Septoria urticæ_. Hence it will be seen how large a number of fungi
may attach themselves to one herbaceous plant, sometimes whilst
living, but most extensively when dead. This is by no means a solitary
instance, but a type of what takes place in many others. If, on the
other hand, we select such a tree as the common lime, we shall find
that the leaves, twigs, branches, and wood bear, according to M.
Westendorp,[G] no less than seventy-four species of fungi, and of
these eleven occur on the leaves. The spruce fir, according to the
same authority, nourishes one hundred and fourteen species, and the
oak not less than two hundred.
It is curious to note how fungi are parasitic upon each other in some
instances, as in that of _Hypomyces_, characteristic of the genus, in
which sphæriaceous fungi make hosts of dead _Lactarii_, &c. We have
already alluded to _Nyctalis_, growing on decayed _Russulæ_, to
_Boletus parasiticus_, flourishing on old _Scleroderma_, and to
_Agaricus Loveianus_, on the pileus of _Agaricus nebularis_. To these
we may add _Torrubia ophioglossoides_ and _T. capitata_, which
flourish on decaying _Elaphomyces_, _Stilbum tomentosum_ on old
_Trichia_, _Peziza Clavariarum_ on dead _Clavaria_, and many others,
the mere enumeration of which would scarcely prove interesting. A very
curious little parasite was found by Messrs. Berkeley and Broome, and
named by them _Hypocrea inclusa_, which makes itself a home in the
interior of truffles. Mucors and moulds flourish on dead and decaying
Agarics, and other fleshy forms, in great luxuriance and profusion.
_Mucor ramosus_ is common on _Boletus luridus_, and _Syzygites
megalocarpus_ on Agarics, as well as _Acrostalagmus cinnabarinus_. A
very curious little parasite, _Echinobotryum atrum_, occurs like
minute nodules on the flocci of black moulds. _Bactridium Helvellæ_
usurps the fructifying disc of species of _Peziza_. A small
_Sphinctrina_ is found both in Britain and the United States on old
_Polypori_. In _Sphæria nigerrima_, _Nectria episphæria_, and two or
three others, we have examples of one sphæriaceous fungus growing
upon another.
Mr. Phillips has recently indicated the species of fungi found by him
on charcoal beds in Shropshire,[H] but, useful as it is, that only
refers to one locality. A complete list of all the fungi which have
been found growing on charcoal beds, burnt soil, or charred wood,
would be rather extensive. The fungi found in hothouses and stoves are
also numerous, and often of considerable interest from the fact that
they have many of them never been found elsewhere. Those found in
Britain,[I] for instance, are excluded from the British Flora as
doubtful, because, growing upon or with exotic plants, they are deemed
to be of exotic origin, yet in very few cases are they known to be
inhabitants of any foreign country. Some species found in such
localities are not confined to them, as _Agaricus coepestipes_,
_Agaricus cristatus_, _Æthalium vaporarium_, &c. It is somewhat
singular that certain species have a predilection for growing in
proximity with other plants with which they do not appear to have any
more intimate relation. Truffles, for instance, in association with
oaks, _Peziza lanuginosa_ under cedar-trees, _Hydnangium carneum_
about the roots of _Eucalypti_, and numerous species of _Agaricini_,
which are only found under trees of a particular kind. As might be
anticipated, there is no more fertile habitat for fungi than the dung
of animals, and yet the kinds found in such locations belong to but a
few groups. Amongst the _Discomycetes_, a limited number of the genus
_Peziza_ are fimicolous, but the allied genus _Ascobolus_, and its own
immediate allies, include amongst its species a large majority that
are found on dung. If we take the number of species at sixty-four,
there are only seven or eight which do not occur on dung, whilst
fifty-six are fimicolous. The species of _Sphæria_ which are found on
the same substances are also closely allied, and some Continental
authors have grouped them under the two proposed genera _Sporormia_
and _Sordaria_, whilst Fuckel[J] proposes a distinct group of
_Sphæriacei_, under the name of _Fimicoli_, in which he includes as
genera _Coprolepa_, _Hypocopra_, _Delitschia_, _Sporormia_,
_Pleophragmia_, _Malinvernia_, _Sordaria_, and _Cercophora_. The two
species of _Pilobolus_, and some of _Mucor_, are also found on dung,
_Isaria felina_ on that of cats, _Stilbum fimetarium_ and a few other
moulds, and amongst Agarics some species of _Coprinus_. Animal
substances are not, as a rule, prolific in the production of fungi.
_Ascobolus saccharinus_ and one or two others have been found upon old
leather. _Onygena_ of two or three species occurs on old horn, hoofs,
&c. Cheese, milk, &c., afford a few forms, but the largest number
infest dead insects, either under the mouldy form of _Isaria_ or the
more perfect condition of _Torrubia_, and occasionally under other
forms.
Robin[K] has recorded that three species of _Brachinus_, of the order
Coleoptera, have been found infected, whilst living, with a minute
yellow fungus which he calls _Laboulbenia Rougeti_, and the same
species has been noted on other beetles. _Torrubia Melolonthæ_[L] has
been described by Tulasne as occurring on the maybug or cockchafer,
which is allied to, if not identical with, _Cordyceps Ravenelii_, B.
and C., and also that described and figured by M. Fougeroux de
Bondaroy.[M] _Torrubia curculionum_, Tul., occurs on several species
of beetles, and seems to be by no means uncommon in Brazil and Central
America. _Torrubia coespitosa_, Tul., which may be the same as
_Cordyceps Sinclairi_, B.,[N] is found on the larvæ of _Orthoptera_ in
New Zealand, _Torrubia Miquelii_ on the larvæ of _Cicada_ in Brazil,
and _Torrubia sobolifera_ on the pupæ of _Cicada_ in the West Indies.
A romantic account is given of this in an extract cited by Dr. Watson
in his communication to the Royal Society.[O] "The vegetable fly is
found in the island Dominica, and (excepting that it has no wings)
resembles the drone, both in size and colour, more than any other
English insect. In the month of May it buries itself in the earth and
begins to vegetate. By the latter end of July, the tree is arrived at
its full growth, and resembles a coral branch, and is about three
inches high, and bears several little pods, which, dropping off,
become worms, and from thence flies, like the English caterpillar."
_Torrubia Taylori_, which grows from the caterpillar of a large moth
in Australia, is one of the finest examples of the genus. _Torrubia
Robertsii_, from New Zealand, has long been known as attacking the
larva of _Hepialus virescens_. There are several other species on
larvæ of different insects, on spiders, ants, wasps, &c., and one or
two on mature Lepidoptera, but the latter seem to be rare.
That fungi should make their appearance and flourish in localities and
conditions generally considered inimical to vegetable life is no less
strange than true. We have already alluded to the occurrence of some
species on spent tan, and some others have been found in locations as
strange. We have seen a yellow mould resembling _Sporotrichum_ in the
heart of a ball of opium, also a white mould appears on the same
substance, and more than one species is troublesome in the opium
factories of India. A mould made its appearance some years since in a
copper solution employed for electrotyping in the Survey Department of
the United States,[P] decomposing the salt, and precipitating the
copper. Other organisms have appeared from time to time in various
inorganic solutions, some of which were considered destructive to
vegetable life, and it is not improbable that some of these organisms
were low conditions of mould. It may well occasion some surprise that
fungi should be found growing within cavities wholly excluded from the
external air, as in the hollow of filberts, and the harder shelled
nuts of _Guilandina_, in the cavities of the fruit of tomato, or in
the interior of an egg. It is scarcely less extraordinary that
_Hypocrea inclusa_ should flourish in the interior of a kind of
truffle.
From the above it will be concluded that the habitats of fungi are
exceedingly variable, that they may be regarded as almost universal
wherever decaying vegetable matter is found, and that under some
conditions animal substances, especially of vegetable feeders, such as
insects, furnish a pabulum for their development.
A very curious and interesting inquiry presents itself to our minds,
which is intimately related to this subject of the habitats of fungi.
It shapes itself into a sort of "puzzle for the curious," but at the
same time one not unprofitable to think about. How is the occurrence
of new and before unknown forms to be accounted for in a case like the
following?[Q]
It was our fortune--good fortune as far as this investigation was
concerned--to have a portion of wall in our dwelling persistently damp
for some months. It was close to a cistern which had become leaky. The
wall was papered with "marbled" paper, and varnished. At first there
was for some time nothing worthy of observation, except a damp
wall--decidedly damp, discoloured, but not by any means mouldy. At
length, and rather suddenly, patches of mould, sometimes two or three
inches in diameter, made their appearance. These were at first of a
snowy whiteness, cottony and dense, just like large tufts of cotton
wool, of considerable expansion, but of miniature elevation. They
projected from the paper scarcely a quarter of an inch. In the course
of a few weeks the colour of the tufts became less pure, tinged with
an ochraceous hue, and resembling wool rather than cotton, less
beautiful to the naked eye, or under a lens, and more entangled. Soon
after this darker patches made their appearance, smaller, dark olive,
and mixed with, or close to, the woolly tufts; and ultimately similar
spots of a dendritic character either succeeded the olive patches, or
were independently formed. Finally, little black balls, like small pin
heads, or grains of gunpowder, were found scattered about the damp
spots. All this mouldy forest was more than six months under constant
observation, and during that period was held sacred from the
disturbing influences of the housemaid's broom and duster.
Curiosity prompted us from the first to submit the mouldy denizens of
the wall to the microscope, and this curiosity was increased week by
week, on finding that none of the forms found vegetating on nearly two
square yards of damp wall could be recognized as agreeing specifically
with any described moulds with which we were acquainted. Here was a
problem to be solved under the most favourable conditions, a forest of
mould indoors, within a few yards of the fireside, growing quite
naturally, and all strangers. Whence could these new forms proceed?
The cottony tufts of white mould, which were the first to appear, had
an abundant mycelium, but the erect threads which sprang from this
were for a long time sterile, and closely interlaced. At length
fertile threads were developed in tufts, mixed with the sterile
threads. These fruit-bearers were shorter and stouter, more sparingly
branched, but beset throughout nearly their whole length with short
patent, alternate branchlets. These latter were broadest towards the
apex, so as to be almost clavate, and the extremity was beset with two
or three short spicules. Each spicule was normally surmounted by an
obovate spore. The presence of fertile threads imparted the ochraceous
tint above alluded to. This tint was slight, and perhaps would not
have been noticed, but from the close proximity of the snow-white
tufts of barren threads. The fertile flocci were decumbent, probably
from the weight of the spores, and the tufts were a little elevated
above the surface of the matrix. This mould belonged clearly to the
_Mucedines_, but it hardly accorded well with any known genus,
although most intimately related to _Rhinotrichum_, in which it was
placed as _Rhinotrichum lanosum_.[R]
The white mould having become established for a week or two, small
blackish spots made their appearance on the paper, sometimes amongst
thin patches of the mould, and sometimes outside them. These spots, at
first cloudy and indefinite, varied in size, but were usually less
than a quarter of an inch in diameter. The varnish of the paper was
afterwards pushed off in little translucent flakes or scales, an
erect olivaceous mould appeared, and the patches extended to nearly an
inch in diameter, maintaining an almost universal circular form. This
new mould sometimes possessed a dirty reddish tint, but was commonly
dark olive. There could be no mistake about the genus to which this
mould belonged; it had all the essential characters of _Penicillium_.
Erect jointed threads, branched in the upper portion in a fasciculate
manner, and bearing long beaded threads of spores, which formed a
tassel-like head, at the apex of each fertile thread. Although at
first reminded of _Penicillium olivaceum_, of Corda, by the colour of
this species, it was found to differ in the spores being oblong
instead of globose, and the ramifications of the flocci were
different. Unable again to find a described species of _Penicillium_
with which this new mould would agree, it was described under the name
of _Penicillium chartarum_.[S]
Almost simultaneously, or but shortly after the perfection of the
spores of _Penicillium_, other and very similar patches appeared,
distinguished by the naked eye more particularly by their dendritic
form. This peculiarity seemed to result from the dwarfed habit of the
third fungus, since the varnish, though cracked and raised, was not
cast off, but remained in small angular fragments, giving to the spots
their dendritic appearance, the dark spores of the fungus protruding
through the fissures. This same mould was also found in many cases
growing in the same spots amongst _Penicillium chartarum_, but whether
from the same mycelium could not be determined.
The distinguishing features of this fungus consist in an extensive
mycelium of delicate threads, from which arise numerous erect
branches, bearing at the apex dark brown opaque spores. Sometimes the
branches were again shortly branched, but in the majority of instances
were single. The septate spores had from two to four divisions, many
of them divided again by cross septa in the longitudinal direction of
the spore, so as to impart a muriform appearance. As far as the
structure and appearance of the spores are concerned, they resembled
those of _Sporidesmium polymorphum_, under which name specimens were
at first published,[T] but this determination was not satisfactory.
The mycelium and erect threads are much too highly developed for a
good species of _Sporidesmium_, although the name of _Sporidesmium
alternaria_ was afterwards adopted. In fresh specimens of this fungus,
when seen _in situ_ by a half-inch objective, the spores appear to be
moniliform, but if so, all attempts to see them so connected, when
separated from the matrix, failed. On one occasion, a very immature
condition was examined, containing simple beaded, hyaline bodies,
attached to each other by a short neck. The same appearance of beaded
spores, when seen _in situ_, was recognized by a mycological friend,
to whom specimens were submitted for confirmation.[U]
The last production which made its appearance on our wall-paper burst
through the varnish as little black spheres, like grains of gunpowder.
At first the varnish was elevated by pressure from beneath, then
the film was broken, and the little blackish spheres appeared. These
were, in the majority of cases, gregarious, but occasionally a few of
the spheres appeared singly, or only two or three together. As the
whole surface of the damp paper was covered by these different
fungi, it was scarcely possible to regard any of them as isolated,
or to declare that one was not connected with the mycelium of the
others. The little spheres, when the paper was torn from the wall,
were also growing from the under surface, flattened considerably by
the pressure. The spherical bodies, or perithecia, were seated on a
plentiful hyaline mycelium. The walls of the perithecia, rather more
carbonaceous than membranaceous, are reticulated, reminding one of
the conceptacles of _Erysiphe_, to which the perithecia bear
considerable resemblance. The ostiolum is so obscure that we doubt
its existence, and hence the closer affinity of the plant to the
_Perisporiacei_ than to the _Sphæriacei_. The interior of the
perithecium is occupied by a gelatinous nucleus, consisting of
elongated cylindrical asci, each enclosing eight globose hyaline
sporidia, with slender branched paraphyses. A new genus has been
proposed for this and another similar form, and the present
species bears the name of _Orbicula cyclospora_.[V]
The most singular circumstance connected with this narrative is the
presence together of four distinctly different species of fungi, all
of them previously unknown and undescribed, and no trace amongst them
of the presence of any one of the very common species, which would be
supposed to develop themselves under such circumstances. It is not at
all unusual for _Sporocybe alternata_, B., to appear in broad black
patches on damp papered walls, but in this instance not a trace was to
be found. What were the peculiar conditions present in this instance
which led to the manifestation of four new forms, and none of the old
ones? We confess that we are unable to account satisfactorily for the
mystery, but, at the same time, feel equally unwilling to invent
hypotheses in order to conceal our own ignorance.
[A] These predilections must be accepted as general, to which there
will be exceptions.
[B] Viviani, "I Funghi d'Italia."
[C] Badham's "Esculent Funguses," Ed. i. pp. 42, 116.
[D] An excellent white Agaric occurs on ant nests in the
Neilgherries, and a curious species is found in a similar
position in Ceylon.
[E] Westendorp, "Les Cryptogams après leurs stations naturelles."
[F] Cooke, "On Nettle Stems and their Micro-Fungi," in "Journ.
Quekett Micro. Club," iii. p. 69.
[G] Westendorp, "Les Cryptogams après leurs stations naturelles,"
1865.
[H] "Gardener's Chronicle," 1874.
[I] W. G. Smith, in "Journ. Botany," March, 1873; Berkeley, in
"Grevillea," vol. i. p. 88.
[J] Fuckel, "Symbolæ Mycologicæ," p. 240.
[K] Robin, "Végét. Parasites," p. 622, t. viii. f. 1, 2.
[L] Tulasne, "Selecta Fung. Carp." iii. p. 12.
[M] "Hist. de l'Acad. des Sciences," 1769. Paris, 1772.
[N] Berkeley, "Crypt. Bot." p. 73; Hooker, "New Zealand Flora," ii.
338.
[O] "Philosophical Transactions," liii. (1763), p. 271.
[P] Berkeley's "Outlines," p. 30.
[Q] "Popular Science Review," vol. x. (1871), p. 25.
[R] Specimens of this mould were distributed in Cooke's "Fungi
Britannici Exsiccati," No. 356, under the name of _Clinotrichum
lanosum_.
[S] Cooke's "Handbook of British Fungi," p. 602.
[T] Cooke's "Fungi Britannici Exsiccati," No. 329, under the name of
_Sporidesmium polymorphum_ var. _chartarum_.
[U] This reminds one of Preuss's _Alternaria_, figured in Sturm's
"Flora;" it has been suggested that the mould, as seen when
examined under a power of 320 diam., is very much like a
_Macrosporium_. Again arises the question of the strings of
spores attached end to end.
[V] "Handbook of British Fungi," vol. ii. p. 926, No. 2,788.
XII.
CULTIVATION.
The cultivation of fungi in this country for esculent purposes is
confined to a single species, and yet there is no reason why, by a
series of well-conducted experiments, means should not be devised for
the cultivation of others, for instance, _Marasmius orcades_, and the
morel. Efforts have been made on the Continent for the cultivation of
truffles, but the success has hitherto been somewhat doubtful. For the
growth of the common mushroom, very little trouble and care is
required, and moderate success is certain. A friend of ours some years
since was fortunate enough to have one or two specimens of the large
puff-ball, _Lycoperdon giganteum_, growing in his garden. Knowing its
value, and being particularly fond of it when fried for breakfast, he
was anxious to secure its permanence. The spot on which the specimens
appeared was marked off and guarded, so that it was never desecrated
by the spade, and the soil remained consequently undisturbed. Year
after year, so long as he resided on the premises, he counted upon and
gathered several specimens of the puff-ball, the mycelium continuing
to produce them year after year. All parings, fragments, &c., not
utilized of the specimens eaten were cast on this spot to rot, so that
some of the elements might be returned to the soil. This was not true
cultivation perhaps, as the fungus had first established itself, but
it was preservation, and had its reward. It must be admitted, however,
that the size and number of specimens diminished gradually, probably
from exhaustion of the soil. This fungus, though strong, is much
approved by many palates, and its cultivation might be attempted.
Burying a ripe specimen in similar soil, and watering ground with the
spores, has been tried without success.[A]
As to the methods adopted for cultivation of the common mushroom,
it is unnecessary to detail them here, as there are several special
treatises devoted to the subject, in which the particulars are
more fully given than the limits of this chapter will permit.[B]
Recently, M. Chevreul exhibited at the French Academy some splendid
mushrooms, said to have been produced by the following method: he
first develops the mushrooms by sowing spores on a pane of glass,
covered with wet sand; then he selects the most vigorous individuals
from among them, and sows, or plants their mycelium in a cellar in
a damp soil, consisting of gardener's mould, covered with a layer
of sand and gravel two inches thick, and another layer of rubbish from
demolitions, about an inch deep. The bed is watered with a diluted
solution of nitrate of potash, and in about six days the mushrooms
grow to an enormous size.[C] The cultivation of mushrooms for the
market, even in this country, is so profitable, that curious
revelations sometimes crop up, as at a recent trial at the Sheriffs'
Court for compensation by the Metropolitan Railway Company for
premises and business of a nurseryman at Kensington. The Railway had
taken possession of a mushroom-ground, and the claim for compensation
was £716. It was stated in evidence that the profits on mushrooms
amounted to 100 or 150 per cent. One witness said if £50 were
expended, in twelve months, or perhaps in six months, the sum
realized would be £200.