_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 stem, has some species which prefer the ground. _Polyporus tuberaster_, P., in Italy springs from the _Pietra funghaia_,[C] 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 _Hymenochoete_, _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_ and _Pistillaria_ are small, growing chiefly on dead herbaceous plants. One or two are developed from a kind of _Sclerotium_, which is in fact a compact perennial mycelium. TREMELLINI.--These curious gelatinous fungi are, with rare exceptions, developed on branches or naked wood; _Tremella versicolor_, B. and Br., one of the exceptions, being parasitic on a species of _Corticium_, and _Tremella epigæa_, B. and Br., spreading over the naked soil. This completes our rapid survey of the habitats of the _Hymenomycetes_. Very few of them are really destructive to vegetation, for the Agarics and Polypori found on growing trees are seldom to be seen on vigorous, but rather on dead branches or partly-decayed trunks. The GASTEROMYCETES are far less numerous in species, and also in individuals, but their habitats are probably more variable. The _Hypogæi_, or subterranean species, are found either near the surface or buried in the soil, usually in the neighbourhood of trees. PHALLOIDEI.--In most cases the species prefer woody places. They are mostly terrestrial, and have the faculty of making their presence known, even when not seen, by the fetid odour which many of them exhale. Some of them occur in sandy spots.