The summit of each basidium is produced generally into four conical points (_sterigmata_, Fig. 145 _b_), from each of which a basidiospore is abstricted. The basidia may be classified into three principal groups, each of which accompanies a distinctive conidiophore: 1, the long, filamentous, _transversely divided_ basidia, with lateral sterigmata and spores, found in the Uredinaceæ (Figs. 146 _D_, 153), Auriculariaceæ (Fig. 160 _B_), and Pilacraceæ; 2, the spherical, _longitudinally divided_ basidia of the Tremellaceæ (Figs. 160 _C d_; 161 iii. iv.); and 3, the ovoid, or cylindrical, _undivided_ basidia of the Autobasidiomycetes (Figs. 145, 163, etc.); the two last have apical sterigmata and spores. The first two groups are the septate basidia (_protobasidia_), of the _Protobasidiomycetes_; while the unseptate basidia (autobasidia) of the _Autobasidiomycetes_ are the third group. On the formation of the basidiospores, the nucleus of the basidium divides into four nuclei, each of which is transferred to a spore. In addition to the basidia, _simple conidiophores_ are also found. In the Protobasidiomycetes, the simple conidia are very generally found as accessory methods of reproduction in conjunction with the basidiospores; but less frequently in the Autobasidiomycetes, _e.g._ among the Dacryomycetes, Tomentellaceæ, _Heterobasidion annosum_. The simple conidiophores vary in size, and in the number and shape of the conidia; they, however, resemble the basidia, and are doubtless an early stage in the development of the definitely formed basidia. Finally, well-defined _chlamydospores_, formed in various ways, appear in the Basidiomycetes as supplementary reproductive bodies (compare p. 90). Among the Protobasidiomycetes, chlamydospores are at present only found among the Uredinaceæ, but in various forms; in the majority of families of the Autobasidiomycetes _oidia_ frequently occur (Fig. 162), but genuine chlamydospores seldom. In the same species several of the known forms of reproduction may be distinguished. The _mycelium_ is generally composed of white, branched strands, consisting of numerous felted hyphæ; in some, sclerotia are found.--The great majority are saprophytes; some (particularly all the Uredinaceæ), are parasites. DIVISIONS OF THE BASIDIOMYCETES. Series 1. PROTOBASIDIOMYCETES: partly gymnocarpic, partly angiocarpic. „ 2. AUTOBASIDIOMYCETES. Family 1. DACRYOMYCETES: gymnocarpic. „ 2. HYMENOMYCETES: partly gymnocarpic, partly hemiangiocarpic. „ 3. PHALLOIDEÆ: hemiangiocarpic. „ 4. GASTEROMYCETES: angiocarpic. Appended. BASIDIOLICHENES: Lichen-forming basidiomycetes. Series I. =Protobasidiomycetes.=