84 Murrill: Polyporaceae of North America 



of its kind in the code, is in danger of being overworked. More- 

 over, I have good reason to know that a mere makeshift of this 

 kind will never be accepted by working mycologists as permanent. 

 Agaricus, then, properly figures as a genus of the Polyporaceae. 



The genus Striglia was founded by Adanson upon Batarra's 

 plate ?£, which represents several common species of Agaricus, 

 the first being A. qucrcinus L. 



Dacdalca of Persoon was founded on D. quercina (L.) and 

 four other species, one of them being D. confragosa. Batarra is 

 quoted at some length and plate jS cited by Persoon, but no 

 mention is made of Striglia, based on the same plate. 



Daedalcopsis, founded upon the single species Daedalea con- 

 fragosa (Bolt.), completes the list of synonyms. 



Species belonging to the genus Agaricus have white or wood- 

 colored context, hyaline spores and poroid, daedaleoid or lamel- 

 loid tubes. One rare species, A. juuiperinus, occurs on coniferous 

 wood ; all the others are found abundantly on decaying wood of 

 various deciduous trees. One species, A. deplanatus, is tropical ; 

 the rest occur in the United States and Canada, and two of these 

 are found also in Europe. Most of the species, in spite of the re- 

 markable variability of some of them, are easily distinguished ; 

 A. Aesculi and A. deplanatus, however, approach very near each 

 other in some of their forms. 



Synopsis of the North American species 



1. Tubes one to several millimeters in transverse diameter; surface usually brown or 



discolored ; plants found in temperate regions. 2. 



Tubes less than one-half millimeter in transverse diameter ; surface white or yel- 

 lowish ; plants found in the southern states or the tropics. 3. 



2. Pileus thick, triangular, margin obtuse ; tubes large, daedaleoid, dissepiments obtuse ; 



context wood-colored ; plants abundant on oak. I. A. quercums. 



Pileus thick, triangular, margin obtuse ; tubes large, daedaleoid, dissepiments ob- 

 tuse; context white ; plants rare on red cedar. 2. A. juniperitius. 



Pileus thin, applanate, multizonate, margin very acute; hymenium poroid, daedaleoid 

 or lamelloid, dissepiments acute. 3- A - confragosus. 



3. Pileus reniform, rigid, usually azonate ; plants found in the southern states. 



4. A. Aesculi. 



Pileus thin, flexible, variously shaped, usually multizonate ; plants confined to the 



tropics. 5- A. deplanatus. 



