454 



CLASS BASIDIOMYCETEAE 



Fig. 150 {Left). Order Tremellales, Family Sirobasidiaceae. Sirobasidium albidum 

 Lagerh. & Pat. (A) Chain of two basidia, the terminal one almost mature. (B) Chain 

 of several basidia, the upper three collapsed, the fourth approaching maturity. (After 

 Lagerheim and Patouillard: /. Botan., 6(24):465-469.) 



Fig. 151 (Right). Order Tremellales, Family Tremellaceae. Pro/o/iz/d/ium geZaiznosw?« 

 (Fr.) Karst. {Tremelodon of most authors). Habit sketch. (After A. MoUer, from 

 Killermann, in Engler und Prantl: Die NatiirUchen Pflanzenfamilien, Zweite Auflage, 

 vol. 6, pp. 99-290, Leipzig, W. Engelmann.) 



mann (1936) and Xenolachne, growing as a parasite on a minute Dis- 

 comycete in Oregon (Rogers, 1947). Hyaloria is stalked and externally 

 gelatinous with the basidia on the head, much overtopped by long hairs 

 (or cystidia). Xenolachne forms a thin film on the apothecium of the host 

 and lacks a gelatinous coat or cystidia but the extremely long extensions 

 of the two-celled basidia, with the basidiospores at the apex give a felty 

 appearance to the fungus. The type of basidium in these two genera 

 resembles that characteristic of most of the Gasteromycetes and for this 

 structure Rogers adopts the name apobasidium proposed by Gilbert 



(1928). 



In the Tremellaceae the genus Stypella produces a small felty mass of 

 tangled, more or less gelatinous hyphae in whose upper layer the basidia 

 arise. These spore fruits are clustered, separate or anastomosing on a dry 

 fioccose subiculum, the whole patch sometimes reaching a diameter of 

 several centimeters. In Sehacina there is a more or less waxy or gelatinous 

 crust with the hyphae of the upper portion directed perpendicularly to 

 the surface, the terminal cells of these rather closely packed hyphae 

 being the basidia. Cushion-like or lobed, gelatinous spore fruits are char- 

 acteristic of Exidia and TremeUa. Gland-like dots occur in the spore fruit 

 of the former and are absent in the latter. The basidiospores of the former 

 are mostly allantoid, those of the latter straight and ellipsoidal to nearly 

 spherical. When these spores germinate the sprout-conidia of Exidia are 

 mostly curved, those of TremeUa yeast-like. 



