456 



CLASS BASIDIOMYCETEAE 



basidium, i.e., is not divided by vertical septa as in the Tremellales nor by 

 transverse septa as in the Auriculariales. The basidial primordium is sub- 

 globose, pyriform or broadly clavate. From the upper portion of this cell 

 arise usually four stout cells which are narrowed at the tip to form a 

 sterigma upon which a single basidiospore is formed. These four cells are 

 considered by Rogers, Martin, and others to be homologous to the stout 

 arms growing out of the four cells of the basidium of the Tremellaceae, 

 and which they call "epibasidia." 



In TulasneUa and Gloeotulasnella the "epibasidia" are separated from 

 the "hypobasidium" by a septum at the base of each. They may remain 

 attached or may fall off. At the apical end they elongate and bear a 

 sterigma on which is borne the nonseptate basidiospore. This spore when 

 set free germinates "by repetition," i.e., it produces a lateral or terminal 

 sterigma and a secondary spore into which the whole cytoplasm and 

 nucleus pass, this spore then being discharged as in the case of the parent 

 spore. These two genera are distinguished as follows: TulasneUa, "arid- 

 pruinose to waxy, basidia not imbedded in a gelatinous matrix; pro- 

 basidia globose to obovate, sessile or with a short scarcely differentiated 

 stalk; epibasidia with subulate tips merging into the sterigmata; gloeocys- 

 tidia never present" (Martin, 1944). A dozen or more species. Gloeotulas- 

 nella, "waxy gelatinous to mucous gelatinous, basidia imbedded in a 

 gelatinous matrix; probasidia clavate capitate, with a more or less 

 cylindrical stalk and a swollen head; epibasidia extended into cylindrical 

 tubular filaments sharply constricted at the base of the sterigmata; 

 gloeocystidia present or absent" (Martin). Ten or more species. The 



B 



Fig. 152. Order Tulasnellales, Family Tulasnellaceae. (A, B) TulasneUa violea 

 (Quel.) Bourd. & Galz. {PachysterigmafugaxSoh^in-Ol&en). (A) Mycelium with several 

 clusters of basidia. (B) Mature basidium. (C) Ceratobasidium cornigerum (Bourd.) 

 Rogers. Basidia and basidiospores in various stages of development. (A-B, after 

 Brefeld: Untersuchungen aus dem Gesammtgebiete der Mykologie, Heft 8, pp. 1-305. 

 C, courtesy, Martin: Univ. Iowa Studies in Natural History, 18(3): 1-88.) 



