138 THE CHICAGO ACADEMY OF SCIENCES 



On the ground, border of ditches. It consists of a broad, 

 indeterminately effused crust, soft when growing but hard and 

 continuous when dry. 



Near Chicago. Harper. 

 Corticium pallescens Schw. 



Broadly effused, agglutinate, in little cartilaginous elevations, 

 hard. 



Hymenium spuriously papillose, cracked, white, becoming 

 pallid; spores globose, 7 to 8 /x. Broadly effused, indeterminate, 

 thick, much cracked when dry, pallid with a tinge of red here 

 and there. Collected by Schweinitz on charred trunks. 



Near Chicago. Harper. 

 Corticium sebaceum Pers. 



Effused, flaxy-waxy, hardening, incrusting, tuberculose or 

 stalactitious, whitish with a similar border. 



Hymenium collapsing, flocculose-pruinose. 



Incrusting various substances. Variable in form, white, the 

 border not fringed or pencillate. 



River Forest, July, 1902. It is Sebacina incrustans Tulasne. 

 Corticium Oakesii B. & C. 



At first pezizaeform with the margin erect, inflexed, white, 

 tomentose, at length confluent. 



Hymenium pale fawn-color. Spores oblong-ellipsoid, 25 x 

 14 ^ 



On bark of Ostrya. Common. According to Fries, this species 

 does not differ from the European C. amorphum, but Cooke 

 insists that it is distinct on account of its more h airy pileus, darker 

 disk and spores not subglobose but oblong-ellipsoid. 



Corticium salicinum Fr. 



Coriaceous, soft, rigid when dry, affixed by the center, the 

 margin everywhere reflexed, wiiite villous externally. 



Hymenium persistently sanguineous, when dry contiguous. 

 Spores cylindric-ellipsoid, curved, 14 to 16 x 5 to 6 /x. 



On dead branches of Salix. Millers. August. Harper. 

 Corticium arachnoideum Berk. 



Thin, effused, pallid, immarginate, fibrillose or subfloccose 

 beneath, circumference fimbriate with white fibrils. 



On rotten wood. Near Chicago. Harper, 

 Corticium vellereum Ell. & Crag. 



Dirty-white, texture loose, floccose, margin byssoid. 

 Spores abundant, globose, 4 to 5 /a. in diameter, borne on short, 

 stout, subclavate basidia. 



On a decorticated log of Tilia a?nericana, River Forest. July. 

 It also occurs on Hicoria. 



