have not suffered much in this country from parasites. Besides these, there are many other less troublesome parasites, such as Uredo filicum, o ferns; Puccinia Lychnidearum, on leaves of sweet-william; Uredo Orchidis, on leaves of orchids, &c.

If we would sum up the influences of fungi in a few words, it could be done somewhat in the following form. Fungi exert a deleterious influence

On Man,

When eaten inadvertently.

By the destruction of his legitimate food.
In producing or aggravating skin diseases.

On Animals,

By deteriorating or diminishing their food supplics.
By establishing themselves as parasites on some species.

On Plants,

By hastening the decay of timber.

By establishing themselves as parasites.
By impregnating the soil.

But it is not proved that they produce epidemic diseases in man or animals, or that the dissemination of their multitudinous spores in the atmosphere has any appreciable influence on the health of the human race. Hence their association with cholera, diarrhoea, measles, scarlatina, and the manifold ills that flesh is heir to, as producing or aggravating causes, must, in the present state of our knowledge and experience, be deemed apocryphal.

XI.

HABITATS.

Ir commonly happens that one of the first inquiries which the student seeks to have answered, after an interest is excited in fungi, is—Where, and under what circumstances, are they to be found? The inexperienced, indeed, require some guide, or much labour will be expended and patience lost in seeking microscopic forms in just such places as they are least likely to inhabit. Nor is it wholly unprofitable or uninteresting for others, who do not claim to be students, to summarize the habitats of these organisms, and learn how much the circumstances of their immediate surrounding elements influence production. For reasons which will at once be recognized by the mycologist, the most satisfactory method of study will be somewhat that of the natural groups into which fungi are divided.

AGARICINI.-There is such a close affinity between all the genera of this group that it will be a manifest advantage to take together all those fleshy pileate fungi, the fruit of which is borne on folded plates or gills. It must be premised of this group that, for the majority, shade, a moderate amount of moisture, and steady warmth, but not too great heat, are required. A stroll through a wood in autumn will afford good evidence of the predilection of Agaricini, as well as some smaller groups, for such spots. A larger proportion will be found in woods, where shade is afforded, than on open heaths or pastures. These wood-loving forms will consist, again, of those which appear on the soil, and those which are found on rotten stumps and decaying trees. Many of those which grow on trees have a

lateral stem, or scarcely any stem at all. It may be remarked, that some species which spring from the soil delight most in the shelter of particular trees. The Agarics of a beech wood will materially differ largely from those in an oak wood, and both will differ from those which spring up beneath coniferous trees.

It may be accepted as true of the largest proportion of terrestrial species, that if they do not spring directly from rotten leaves, and vegetable débris in the last stage of decay, the soil will be rich in vegetable humus. A few only occur on sandy spots. The genus Marasmius is much addicted to dead leaves; Russula, to open places in woods, springing immediately from the soil. Lactarius prefers trees, and when found in exposed situations, occurs mostly under the shadow of trees.* Cantharellus, again, is a woodland genus, many of the species loving to grow amongst grass or moss, and some as parasites on the latter. Coprinus is not a genus much addicted to woods, but is rather peculiar in its attachment to man-if such expression, or one even implying domesticity, might be employed-farmyards, gardens, dunghills, the base of old gateposts and railings, in cellars, on plaster walls, and even on old damp carpets. Hygrophorus loves "the open," whether pastures, lawns, heaths, commons, or up the slopes of mountains, nearly to the top of the highest found in Great Britain. Cortinarius seems to have a preference for woods, whilst Bolbitius affects dung, or a rich soil. Lentinus, Panus, Lenzites, and Schizophyllum all grow on wood. Coming to the subgenera of Agaricus, we find Pleurotus, Crepidotus, Pluteus, Collybia, Pholiota, Flammula, Hypholoma, and some species of Psathyra growing on wood, old stumps, or charcoal; Amanita, Tricholoma, and Hebeloma most attached to woods; Clitocybe and Mycena chiefly amongst leaves; Nolanea amongst grass; Omphalia and Galera chiefly in swampy places; Lepiota, Leptonia, Psalliota, Stropharia, Psilocybe, and Psathyrella mostly in open places and pastures; Deconica and Panaeolus mostly on dung; Entoloma and Clitopilus chiefly terrestrial, and the rest variable.

* These predilections must be accepted as general, to which there will be exceptions.

Of special habitats, we may allude to Nyctalis, of which the species are parasitic on dead fungi belonging to the genus Russula. One or two species of Agaricus, such as Agaricus tuberosus and Agaricus racemosus, P., grow on decaying Agarics, whilst Agaricus Loveianus flourishes on Agaricus nebularis even before it is thoroughly decayed. A few species grow on dead fir cones, others on old ferns, &c. Agaricus cepostipes, Sow., probably of exotic origin, grows on old tan in hothouses. Agaricus caulicinalis, Bull, flourishes on old thatch, as well as twigs, &c. Agaricus juncicola, Fr., affects dead rushes in boggy places, whilst Agaricus affricatus, Fr., and Agaricus sphagnicola, B., are attached to bog moss in similar localities. Some few species are almost confined to the stems of herbaceous plants. Agaricus petasatus, Fr., Agaricus cucumis, P., and Paxillus panuoides, F., have a preference for sawdust. Agaricus carpophilus, Fr., and Agaricus balaninus, P., have a predilection for beech mast. Agaricus urticæcola, B. and Br., seems to confine itself to nettle roots. Coprinus radians, Fr., makes its appearance on plaster walls, Coprinus domesticus, Fr., on damp carpets. The only epizoic species, according to M. Fries, is Agaricus cerussatus v. nauseosus, which has been met with in Russia on the carcase of a wolf; this, however, might have been accidental. Persoon described Agaricus Neapolitanus, which was found growing on coffee-grounds at Naples; and more recently Viviani has described another species, Agaricus Coffee, with rose-coloured spores, found on old fermenting coffeegrounds at Genoa.* Tratinnick figures a species named Agaricus Markii, which was found in wine casks in Austria. A Coprinus has, both in this country and on the Continent, been found, after a very short time, on the dressing of wounds, where there has been no neglect. A curious case of this kind, which at the time excited great interest, occurred some fifty years since at St. George's Hospital. Some species appear to confine themselves to particular trees, some to come up by preference on soil in garden pots. Certain species have a solitary, others a gre garious habit, and, of the latter, Agaricus grammopodius, Bull,

* Viviani, "I Funghi d'Italia."

Agaricus gambosus, Fr., Marasmius oreades, Fr., and some others grow in rings. Hence it will be seen that, within certain limits, there is considerable variation in the habitats of the Agaricini.

Boleti do not differ much from Agaricini in their localization. They seem to prefer woods or borders of woods to pastures, seldom being found in the latter. One species, B. parasiticus, Bull, grows on old specimens of Scleroderma, otherwise they are for the most part terrestrial.

Polypori also have no wide range of habitat, except in choice of trees on which to grow, for the majority of them are corticolous. The section Mesopus, which has a distinct central steni, has some species which prefer the ground. Polyporus tuberaster, P., in Italy springs from the Pietra funghaia,* and is cultivated for food as well as Polyporus avellanus, which is reared from charred blocks of cob-nut trees.

In other genera of the Polyporei similar habitats prevail. Merulius lacrymans, Fr., one form of dry rot, occurs in cellars, and too often on worked timber; whilst Merulius himantoides, Fr., is much more delicate, sometimes running over plants in conservatories.

HYDNEI.-There is nothing calling for special note on the habitats of these fungi. The stipitate species of Hydnum are some of them found in woods, others on heaths, one on fir-cones, while the rest have similar habitats to the species of Polyporus.

AURICULARINI. The genera Hymenochote, Stereum, and Corticium, with some species of Thelephora, run over corticated or decorticated wood; other species of Thelephora grow on the ground. The Pezizoid forms of Cyphella and Solenia, like species of Peziza, sometimes occur on bark, and of the former genus some on grasses and others on moss.

CLAVARIEI. The interesting, often brightly-coloured, tufts of Clavaria are usually found amongst grass, growing directly from the ground. Only in rare instances do they occur on dead leaves or herbaceous stems. Calocera probably should be classed with the Tremellini, to which its structure seems more closely allied. The species are developed on wood. The species of Typhula

*Badham's " Esculent Furguses," Ed. i. pp. 42, 116.