Fig. 181.—I Hymenogaster citrinus (nat. size); II longitudinal section through H. tener (× 5); III portion of a section of H. calosporus; g a chamber; h hymenium; sp. spores; t trama (× 178); IV Rhizopogon luteolus (nat. size); V Scleroderma vulgare, VI section of V; VII basidia with spores belonging to the same Fungus.
Order 3. Sclerodermataceæ. Capillitium wanting. The peridium is simple and thick, gleba with round, closed chambers, which are filled with basidia.
Scleroderma has a corky peridium. The fruit-bodies commence their development under ground. S. vulgare (Fig. [181] V-VII), has a hard, slaty-black gleba.
Order 4. Nidulariaceæ (Nest-Fungi). Small Fungi of which the fruit-body at first is spherical or cylindrical but upon maturity it becomes cupular or vase-like, and contains several lenticular “peridiola” lying like eggs in a nest. The peridiola are the chambers which contain the hymenium, covered by a thin layer of the gleba, all the remaining portion of the gleba becoming dissolved. On decaying wood.
Nidularia has spherical fruit-bodies containing a large number of lenticular peridiola, embedded in a slimy mass.—Crucibulum has fruit-bodies resembling crucibles with discoid peridiola, each with a spirally-twisted stalk.—Cyathus has a fruit-body, which when open is campanulate, with stratified peridium, and long-stalked, lense-shaped peridiola.
Order 5. Hymenogastraceæ. Fruit-bodies tubercular, globose and subterranean, resembling very closely the Truffles, from which they can only be distinguished with certainty by microscopic means. The peridium is simple, capillitium wanting, and the gleba encloses a system of labyrinthine passages covered with a continuous hymenium. The fruit-bodies persist for some time, and form a fleshy mass, the spores being only set free by the decay of the fruit-body, or when it is eaten by animals. The majority are South European. Hymenogaster, Melanogaster, Rhizopogon (Fig. [181] I-IV).
Appendix to the Basidiomycetes:
Basidiolichenes (Lichen-forming Basidiomycetes).
Several Fungi belonging to the Basidiomycetes have a symbiotic relationship with Algæ exactly similar to that enjoyed by certain Ascomycetes, and these are therefore included under the term Lichens (p. [136]). They are chiefly tropical.