110 



Mycologia 



Cerrena unicolor (Bull.) Murrill 



Daedal e a unicolor Fries 

 One-colored Cerrena 



Plate 6. Figure 6. X i 



Pileus coriaceous, sessile, imbricate, dimidate to flabelliform, 

 conchate, often laterally confluent, 2.5-3.5 X 5-10 X 0.1-0.3 cm - > 

 surface villose-strigose, rugose, zonate, plicate, isabelline to ful- 

 vous, becoming avellaneous with age and blackish and nearly 

 glabrous behind; margin acute, undulate to lobed, paler, zonate, 

 strigose-tomentose ; context very thin, membranous, white, homo- 

 geneous, scarcely 1 mm. thick ; tubes decurrent, labyrinthiform, 

 1-3 mm. long, white or isabelline to fuliginous or umbrinous, 

 averaging 2 to a mm., edges acute, uneven, soon becoming den- 

 tate-lacerate, giving the hymenium an irpiciform appearance; 

 spores ovoid, smooth, hyaline, 4-6 X 3~4^; cystidia none. 



Very common on dead wood in the north temperate zone. It 

 has been found to be parasitic on several deciduous trees. The 

 walls of the furrows soon split up into teeth resembling those of 

 Coriolus prolificans or some species of Hydnum or Irpex. 

 New York Botanical Garden. 



