2 



Mycologia 



On bark or wood of Alnus, Amelanchier, Fagus, Gleditsia, 

 Quercus, and probably other deciduous trees ; rarely on the ground 

 or at the base of stumps, and then often encircling grass, weed 

 stems, etc., in its growth. 



Specimens Examined: Syracuse, N. Y. ; Dayton and Oxford, 

 Ohio (two collections) ; New Richmond and Ann Arbor, Mich.; 

 St. Croix River, Minn. ; St. Louis, Mo. ; Fayetteville, Ark. 



The writer's acquaintance with this species dates back to 1910, 

 when it was collected at Oxford, Ohio, by Miss Audrey Richards 

 and turned over to him for examination. Another collection was 

 made in 191 1, and in 1912 it was found growing on the ground 



Fig. i. P. ambigua. a, Hypha from the trama ; b, Hypha from the subic- 

 ulum ; c, Larger type of hypha usually present ; d, Spores. 



in the garden of Professor Bruce Fink at Oxford. This latter 

 collection was sent to Bresadola, who referred it to P. ambigua, 

 described by him from Europe in 1897. 



When fresh and growing, the color is white or dirty white, and 

 the consistency of the fungus is soft but not watery. Older speci- 

 mens, especially on drying, are apt to become darker, approaching 

 cinnamon in color, but the affinities of the species are with the 

 white Porias. 



The tubes vary considerably in size, and there are always a con- 

 siderable number that are inversely conical or funnel-shaped, per- 

 haps due to the coalescence of two or more of them, as these are 

 always larger than those that retain their cylindrical shape. The 



