160 AGARICALES 



2. Hymenium modified into teeth, tubes or gills 



a. Hymenium of teeth or tooth-like granules Hydnaceae p. 162 



b. Hymenium of tubes or pores Polyporaceae p. 163 



c. Hymenium of gills or rarely of gill-like veins Agaricaceae p. 164 



The line of evolution is practically continuous from the Thelephoraceae through 

 Hydnaceae and Polyporaceae to the Agaricaceae, while the Clavariaceae are prob- 

 ably a lateral offshoot of the first family. The Hypochnaceae may be regarded as 

 primitive or reduced forms, but the predominance of parasitism indicates the latter, 

 corresponding to Exascaceae among Ascomycetes. 



Family 70. HYPOCHNACEAE 



Killermann 131-133 



Pileus lacking or byssoid, rarely somewhat crustose, mostly parasitic and often 

 forming galls; hymenium loose, of simple clavate basidia mostly with 2-6 sterig- 

 mata; spores typically simple, hyaline or colored, smooth or spiny. 



A. Pileus present, byssoid, loose; saprogenous as a 



rule 



1. Spores globose or subglobose, spinose or asper- 



ate, usually yellow; basidia 4- (2-6) sterigmate 



a. Cystidia present Tomentellina K 134 



b. Cystidia lacking Hypochnus 6:653, K 133; 42 



2. Spores cylindric to bacillar, smooth; basidia 



6-x-sterigmate Aureobasis 11:131, K 134 



B. Pileus reduced to a loose group of basidia; typi- 



cally biogenous and usually folicole 



1. Spores 1-celled 



a. Spores globose; basidia obpiriform, 2-sterig- 



mate Urobasidium 11:131, K 131 



b. Spores oblong to fusoid 



(1) Basidia cylindric, 2-sterigmate Kordyana 16:199, K 132 



(2) Basidia clavate, x- (mostly 6) sterigmate Microstroma 4:9, K 131; 53 



2, Spores finally x-celled, mostly curved; basidia 



4-sterigmate 



(1) Cystidia present, clavate, fascicled Botryoconis 



(2) Cystidia lacking or not fascicled Exobasidium 6:664, K 131; 42 



Family 71. THELEPHORACEAE 



6:513; K 135 



Pileus resupinate to dimidiate, funnelform or cupuloid, leathery or membra- 

 nous, more rarely waxy, fleshy, gelatinous or corky; hymenium superior, inferior or 

 amphigenous, smooth or with flat tubercles or ridges; cystidia or papillae fre- 

 quently present, highly variable; spores simple, hyaline or dark. 



Generic distinctions are exceedingly difficult to draw in this family on the 

 basis of form, texture and hymenial surface, and this difficulty has been aggravated 

 by the attempt to base genera upon the form of the various outgrowths of the 

 hymenium. The terminology employed for these has been indefinite and con- 

 fused, and it is impossible to draw a clear line between papillae, spines, cystidia, 

 gloeocystidia and paraphyses (dendrophyses, dichophyses, etc.). 



