Notes and Brief Articles 



49 



Bresadola saw Persoon's specimens and knew the plant well in 

 its various stages, as found abundantly in central and southern 

 Europe on dead wood of oak, aspen, ash, cherry, olive, etc. He 

 describes it as follows : 



" Species haec, omnium comunissima in Europa media, videtur 

 in Suecia deesse, nam neque in Herbario Friesii, neque in col- 

 lectione Romell inveni. Perennans est, stratosa, poris angulatis, 

 mediis, integris, saepe obliquis ; sporis obovatis, uno apice trun- 

 catis, hyalinis, 5-6,5 X 5-5~5 /*> una alterave etiam subangulato- 

 polygonali ; hyphis subhymenialibus, 1.5-2 /x." 



According to Schroeter, the spores are 4.5 X 3-4 /* and the 

 species occurs on both deciduous and coniferous wood the whole 

 year through. I have not seen specimens taken from coniferous 

 wood either in this country or in Europe. 



In America, there has been considerable confusion regarding 

 this species. Schweinitz called it P. obducens because it was 

 stratose ; Morgan associated it with P. xantholoma because it was 

 often yellow ; and Ellis named his specimens P. obducens, P. vul- 

 garis, P. pulchella, etc., according to the vagaries of Cooke and 

 his other advisers. 



And there is more than one good reason for this confusion. 

 When I compared our American specimens with those of Per- 

 soon, I could hardly believe they were the same species ; and it 

 required a close study of hundreds of specimens from various 

 regions and different hosts to connect up the series satisfactorily. 

 This is often the case, however, with species so widely distributed, 

 since there is every reason for them to vary widely. 



I have on the table before me several specimens from Bresa- 

 dola. The thin forms of one or two years' growth agree per- 

 fectly with the types of P. pulchella and other large-pored forms 

 found especially on oak in America. A fine collection from Tol- 

 land, Colorado, is eminently typical of the European plant. The 

 older, stratose specimens from Bresadola, however, agree with 

 the older specimens found abundantly in New York and New 

 Jersey on fallen branches of various kinds, which in their early 

 stages appear quite distinct from the European forms that I have 

 seen. Morgan describes this young stage as follows : 



