366 Murrill: Polyporaceae of North America 



Types of P. plebcius cubensis also agree with the above, though 

 the specimens are older and more or less encrusted with a dark 

 purplish covering. 



Few polypores are more common in Cuba than this one and 

 a good series of specimens showing nearly all known variations 

 may often be picked from one log. There are, however, in the 

 collection here some plants from Florida which show two varia- 

 tions not yet seen in specimens from elsewhere. Some of these 

 have the context and pores nearly white, instead of olive-colored, 

 and others show distinctly daedaleoid variations in the hymenium. 

 How much the steam treatment used by Calkins may have affected 

 these specimens it is difficult to say. 



This species occurs on fallen deciduous wood throughout 

 tropical America and the states bordering the gulf of Mexico, 

 being found as far north as South Carolina. 



Ell. & Ev. N. A. Fung. 1704; Georgia, Ravenel, Harper ; 

 South Carolina, Ravenel ; Alabama, Earlc, Baker, Underwood ; 

 Louisiana, Langlois, Lloyd; Texas, Hodson ; Florida, Martin, 

 Ran, Calkins, Rolfs, Ives ; Cuba, Wright 232, Earle 133, Parle & 

 Wilson 2 jo, Parle & Underwood 388, 11 23, 1501, 1523, Parle & 

 Murrill 107, 205, 224, 230, 253, 342, 338, 360, 370, 483, 327, 

 393 ; Porto Rico, Parle 169, 171 ; Jamaica, Underwood 2324, 

 2832, 2833, Parle 243 a ; Nicaragua, C. L. Smith 74. 



3. Amauroderma gen. nov. 



Type : Amauroderma regulicolor (Cke.) Murr. 



Hymenophore large, epixylous, stipitate, the stipe often much 

 elongated ; surface smooth, encrusted, not varnished : context 

 brown, punky ; tubes cylindrical, concolorous, the mouths usually 

 light-colored at first : spores ovoid or globose, brown. 



The generic name here employed was used by Patouillard 

 (Tax. Hymen. 105. 1900) for a subdivision of the genus Gano- 

 derma, referring to the dark, namely, not shining, surface of cer- 

 tain species. Members of the genus within our limits are confined 

 to the tropics. 



Synopsis of the rcortli American species 



1. Pileus less than 5 cm. in diameter, simple, tubes 8 to a mm. I. A. regulicolor. 

 Pileus 10 cm. or more in diameter. 2 - 



2. Stipe laterally attached, plants cespitose, tubes 5 to a mm. 2. A. coffeatum. 

 Stipecentrallyattached,plantssimple,sporesspherical,echinulate. 3. A. Chaperi. 



