Structure and Nature of Tremella mycetophila Peck. 



By Edward A. Burt 



( With Plate 23 ) 



* 



During protracted wet weather in August, Tremella mycetophila 

 Peck is occasionally found in northern New York and Vermont on 

 the sterns and pilei of Collybia dryophila. Its fructifications occur 



■ 



as distortions on the host plant and are conspicuous and character- 

 istic, as shown in Fig. 1, which is a copy of the illustration given 

 with the original description.* These distorting fructifications 

 sometimes become an inch in diameter (Fig. 2) and are then thin- 

 walled, hollow sacs, as shown in section in Fig. 3. 



In the original description, the fructifications are stated to be 

 tremelloid-fleshy, but this term seems to me to be applicable only 

 to old specimens collected during rainy weather ; under more 

 normal conditions the fungus is simply fleshy. That the substance 

 is fleshy rather than tremelloid or gelatinous is shown also by the 

 dried specimens, which do not assume the appearance of dried 

 gum or resin upon drying and do become soft and pliant much 

 more readily upon being moistened than is the case with tremel- 

 loid species. 



Several collections of Tremella mycetophila which have been 

 made in recent years and an especially fine specimen contributed 

 by Professor Peck last August, while we were at Floodwood, N. 

 Y., and preserved in alcohol, have made it possible to supply the 

 microscopical characters for this fungus and to give its generic 

 location on the basis of this more complete knowledge of its nature. 



Vertical sections of the fructifications show at the surface a 

 hymenium consisting of basidia of the usual simple, cylindric type, 

 40 x 5— 7j", each bearing at its outer end on short sterigmata four 

 hyaline spores (Figs. 4, 5). These basidiospores are even, inequi- 

 lateral or slightly curved, 5-7 x i%-2 l /i ft (Fig. 6); they are 

 white when collected in quantity on a glass slip. 



* Rep. N. Y. Mus. 28 : 53. //. /. /. 4. 1879 



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