672 ALEURODISCTTS. CORTICIUM 



blue with iodine; basidia 60-90 x 10-14//,. Paraphyses or sterile 

 basidia torulose, 5-9 ^u, in diam. Hyphae rather thick walled, 3 5jn in 

 diam." Bourd. & Galz. Trunks, and branches of oaks. Oct. March. 

 Uncommon. 



**Spores rough. 



2280. A. amorphus (Pers.) Rabenh. (= Corticium amorphum (Pers.) 

 Fr.) cifj(,op(f)o<>, misshapen. 



R. 3-15 mm., white, becoming pallid, cup-shaped, then flattened, 

 scattered, or confluent, externally white tomentose, and hairs incrusted 

 with calcium oxalate; margin free, incurved. Hymenium orange, or 

 buff pink, becoming paler, especially at the margin and subolivaceous 

 when dried, even, continuous, pulverulent. Flesh pale, subcoriaceous, 

 pliant, dense. Spores white, minutely echinulate, spines hyaline, sub- 

 globose, 20-30 x 17-25/t, the membrane colours blue with iodine; 

 "basidia 100-150 x 15-24 /z, with 2-4 subulate, curved sterigmata, 

 20-30 x 4-5 jit. Paraphyses or sterile basidia torulose, 4-lOju, in diam. 

 Hyphae rather thick walled, 3-6 /A in diam., basal hyphae slightly 

 coloured, often incrusted with calcium oxalate" Bourd. & Galz. 

 Silver fir, and larch. Aug. Jan. Uncommon, (v.v.) 



II. Resupinate, effused, margin never reflexed. 



2281. A. acerinus (Pers.) von Hoehn. & Litsch. (= Stereum acerinum 

 (Pers.) Fr.) Acerinus, pertaining to maples. 



R. 3-10 mm., white, irregularly effused, scattered, resupinate, crus- 

 taceous, adnate; margin abrupt. Hymenium white, mealy, then 

 smooth, and finally cracked. Flesh white, chalky, containing numerous 

 crystals of calcium oxalate, compact, thin. Spores white, "ovoid, 

 elliptical, 10-15 x 6-11 p,, scarcely coloured by iodine; basidia 36- 

 50-60 x 6-9-14 ju,, with 2-4-sterigmata, 6-7^, long. Paraphyses or 

 sterile basidia branched, pointed, or capped by 1-2-globules. Hyphae 

 very much branched, -75-1-5^ in diam." Bourd. & Galz. Maple, and 

 sycamore. Dec. Rare. 



Corticium (Pers.). 

 (Cortex, bark.) 



Receptacle waxy, crustaceous, or floccose, resupinate, effused. 

 Hymenium smooth, or tubercular, waxy, continuous, often cracked. 

 Spores white, very rarely coloured, ovate, elliptical, globose, oboval, 

 pip-shaped, pyriform, boat-shaped, almond-shaped, subtriangular, 

 cylindrical, cylindric ellipsoid, oblong, or sausage-shaped; smooth, 

 rarely granular; basidia with 2-4-6-8-sterigmata, forming a homo- 

 geneous hymenium, sometimes accompanied with sterile basidia 

 (cystidioles). Cystidia none. Growing on wood, more rarely on leaves, 

 or on the ground. 



