142 ] The Classification of Lower Organisms 



less compact than a stroma. Fusarium, an enormous number of species producing as 

 conidia crescent-shaped rows of cells. Snyder and Hansen (1941, 1945) find that 

 the fruiting stages are species of Hypomyces, Nectria, Gibberella, or Calonectria, all 

 Hypocreales. 



Family 2. Stilbellacea [Stilbellaceae] Bessey Morph. and Tax. Fungi 584 (1950). 

 Family .Siz/^e'a^ Saccardo Sylloge 4: 563 ( 1886). .S^z/foacfflP Saccardo ( 1889). Family 

 Stilbaceae Lindau (1900); Bessey observed that the type of the genus Stilbum does 

 not belong to this family. Mostly molds producing coremia. 



Family 3. Dematiea [Dematieae] Saccardo Sylloge 4: 235 (1886). Dematiaceae 

 Saccardo (1889). Family Dematiaceae Lindau (1900). Dark-colored parasites, as 

 Helminthosporium, Cladosporium, and Cercospora, or molds, as Alternaria. 



Family 4. Moniliacea [Moniliaceae] Clements Gen. Fung. 138 (1909). Mucedineae 

 Persoon, family Mucedineae or Mucedinaceae Saccardo, not based on a generic 

 name. White or brightly colored parasites or molds, as Oidium, with colorless spores 

 in chains, Monilia, Botrytis, etc. The parasites on animals which have been referred 

 to Monilia are currently called Candida. 



Family (?') 5. Sterile mycelia. Many mycorhizae must be left here. Rhizoctonia, 

 dark net-like masses of hyphae occurring as parasites or saprophytes. Trichophyton, 

 parasitic on the skins of man and animals, causing ringworm, athlete's foot, etc. 



Class 4. BASSDIOMYCETES (Sachs ex Bennett and Thistleton-Dyer) 



Winter 



Order Basidiosporeae and subordinate group Basidiomycetae Cohn in Hedwigia 

 11: 17 (1872). 



Basidiomyceten Sachs Lehrb. Bot. ed. 4: 249 (1874). 



Basidiomycetes Bennett and Thistleton-Dyer in Sachs Textb. Bot. English ed. 

 847 (1875). 



Class Basidiomycetes Winter in Rabenhorst Kryptog.-Fl. Deutschland 1, Abt. 

 1: 72 (1884). 



Classes Teliosporeae and Basidiosporeae Bessey in Univ. Nebraska Studies 7 : 305, 

 306 (1907). 



Classes Teliosporeae and Basidiomycetae Schaffner in Ohio Naturalist 9 : 450 

 (1909). 



Inophyta which produce, as a feature of the sexual cycle, conidiophores called 

 basidia, each producing typically four conidia called basidiospores. 



Germinating basidiospores give rise to mycelia of cells with solitary haploid 

 nuclei. Syngamy occurs among cells of these mycelia, usually simply by contact of 

 vmdifTerontiated cells; the rusts produce differentiated sperms in spermagonia re- 

 sembling the pycnidia of Ascomycetes. In some species any haploid hypha may 

 conjugate with any; in some there are two mating types, and in some four. Raper 

 (1953) has studied the interesting genetics of the mating types. 



The cell produced by .syngamy remains undifferentiated, but gives rise, by con- 

 current division of its nuclei, to a dikaryote mycelium. The nuclei are minute, and 

 mitosis has rarely been seen. The nuclear divisions are often followed by a peculiar 

 manner of cell division, comparable to the crozier formation of Ascomycetes, and 

 producing structures called clamp connections. 



Either the original haploid mycelium or the dikaryophase may produce conidia 

 without nuclear change. Such reproduction is familiar among the rusts, rather un- 

 familiar among other Basidiomycetes. 



