Murrill: Light-Colored Resupinate Polypores 89 



21. Poria vulgaris (Fries) Cooke, Grevillea 14: 109. 1886 

 Polyporus vulgaris Fries, Syst. Myc. 1 : 381. 1821. 



Fries found this species very common throughout the entire 

 year on fallen wood of pine and other trees, as well as upon 

 leaves. He describes it as follows : 



" Longe efTusus, tenuis, siccus, laevis, albus, poris exiguis 

 aequalibus. 



" Ad longitudinem usque pedalem efTusus, laevis, V2. lin. crassus, 

 detritus immutabilis, nec nisi in f rustulis a ligno separabilis ; 

 margine praecipue junioris tenuissime pubescente. Pori recti 

 vel obliqui, subrotundi." 



In Saccardo's " Sylloge " it is reported on the wood of various 

 hardwood trees and conifers from widely separated temperate 

 and tropical regions. Bresadola discusses the species at length in 

 his paper on fungi collected in Hungary and finds it difficult 

 because it is so frequently sterile. He states that Polyporus 

 luteoalbus P. Karst., occurring on fir wood and always sterile, is 

 P. vulgaris Fries of the " Systema " ; and that forma calcea of 

 Fries is also sterile. The typical form, according to him, occurs 

 on the wood of frondose trees and is always fertile, the spores 

 being obovoid, hyaline, 3.5-4 X 2-2.5 /x. I have good specimens 

 from him of this form and can match them fairly well with 

 American material, although the species cannot by any means be 

 called common with us. 



I have seen the specimens in the Fries Herbarium, which are 

 not very satisfactory, and have one sent by him to Massee, which 

 agrees for the most part with those from Bresadola. If we ac- 

 cept Bresadola's interpretation, we have a species with regular, 

 glistening tubes, which are smaller and usually shorter than those 

 of P. subacida and do not become so yellow with age or on drying. 

 From P. vapor aria, it differs decidedly in microscopic characters 

 and the tubes are easily distinguished. P. mollusca is much 

 softer and yellower, although Fries included it as his variety 

 lutescens. 



The following specimens, mostly European, have been ex- 

 amined in the herbarium here. A good hunt would doubtless 

 bring more to light. 



