EADTJLUM. 171 



On dead bark of various trees. Patches 1-6 in. across, 

 closely adnata, thickness variable, tubercles often adpressed 

 or pendulous. 



Very variable, generally originating beneath the epidermis ; 

 2—3 in. broad, quite membranaceous or above 2 lines thick, 

 margin byssoid, occasionally showing a disposition to become 

 reflexed ; hymenium consisting of irregularly disposed, 

 oblique or erect, tooth-Uke, obtuse, entire or laciuiated, 

 often fasciculate tubercles ; the apices sometimes somewhat 

 tomentose. Occasionally they are much scattered and almost 

 resemble spines. (Berk.) 



Pileus entirely resupinate, one to several inches in diameter, 

 at first circular, afterwards irregular and often confluent, of 

 a white colour, mostly changing (especially in the centre) 

 to a pale orange-yellow; margin filamentous, radiating, 

 somewhat raised, or rather thickened. Hymenium composed 

 of processes, irregularly distributed over the surface of the 

 pileus, and more or less distinct. They are singularly 

 variable in their form, but are mostly 2-3 lines in length, 

 slightly compressed, and somewhat broader at the apex than 

 at the base. Often several are confluent, and altogether 

 deformed. At their apex they are generally entire, and 

 sometimes naked, but more frequently villose. In regard to 

 direction, I have seen them both erect and oblique, or even 

 closely appressed. (Grev.) 



Radulura quercinum. Fr. 



Closely adnate subrotund, then irregularly and broadly 

 effused for several inches ; white, then pallid or with a flesti 

 tinge sometimes ; tubercles stout, 2-3 lines long, often fas- 

 ciculate, apex minutely spinulose ; spores broadly elliptical 

 with an oblique apiculus, 7 x 5 ^u. 



Radulum quercinum. Fries, Epicr., p. 525; Stev., Fung., 

 p. 494. 



On dead wood. Distinguished by the villose or spinulose 

 tips of the tubercles and the spores. The above measure- 

 ments are from a specimen from Fries in Berkeley's herba- 

 rium. Often confounded with species of Irpex in herbaria. 



Adnate, persistent, 2—3 in. long, according to Fries, but 

 Berkeley has seen specimens as follows : sometimes a foot or 

 more broad, white when young, then yellowish rufous. 



