TREMELLALES 281 



Dangeard, p. a., "iVIemoire sur la reproduction sexuelle des Basidiomy- 

 cetes," Botcmiste, ^; 119-181, 1895. 



Gilbert, E. M., "Cytological studies of the lower Basidiomycetes. I. Dacry- 

 myces," Tran's. Wis. Acad. Sci., 20: 387-397, 1921. 



IsTVANFFi, G., "ijber die RoUe der Zellkeme bei der Entwicklung der Pilze," 

 Ber. dent, botan. Ges., 13: 452-467, 1895. 



JuEL, H. O., "Die Kerntheilungen in den Basidien und die Phylogenie der 

 Basidiomyceten," Jahrb. iviss. Botan., 52:361-388, 1898. 



Maire, R., "Recherches cytologiques et taxonomiques sur les Basidiomy- 

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Tremellales 



The Tremellales include heterobasidiomycetous jelly fungi in 

 which the basidium is of the so-called cruciate type. The basal 

 portion of the basidium [the hypobasidium of Neuhoff (1924)] is 

 longitudinally septate and is composed of 4 cells, from each of 

 which arises a prolongation (the epibasidium) bearing the spore. 

 About 100 species that have been distributed among 20 genera 

 are included in the order. They are dispersed among 3 or pos- 

 sibly 4 families. The vast majority of the species are wood- 

 inhabiting saprophytes; a few, among which is Tre7nella myce- 

 tophila on the gills of various agarics, are parasitic. At least 1 

 species, T. fiiciformis, is considered edible. Like other Hetero- 

 basidiomycetes, the Tremellales are primarily tropical in their 

 distribution. 



Of the 3 families accepted by most authorities, the Tremella- 

 ceae, with the vast majority of the species, includes all forms in 

 which the basidia are borne singly and freely exposed. In the 

 Hyaloriaceae the fruiting bodies are angiocarpous, the basidia be- 

 ing enclosed within sterile tissue. The Sirobasidiaceae include the 

 species in w^hich the basidia are produced successively in chains. 



The various genera of the Tremellaceae display great diversity 

 in the gross structure of their fruiting bodies. In texture, also, 

 the reproductive structures may vary from gelatinous to waxy or 

 cartilaginous. In one of the simpler genera, Sebacina, the fruiting 

 body is resupinate. In Exidia and Tremella the fructifications 

 may be simple pulvinate masses, or they may be variously lobed, 

 branched, or cerebriform and in some cases appear very similar 

 to those in Auricularia. The genera Clavariopsis and Tremello- 

 dendron resemble Clavaria somewhat, and the toothed hymenia 

 of Protohydnum and Tremellodon are strikingly similar in ap- 



