274 THE PLANT WORLD 



and untrammeled by strained classifications of vegetation, 

 mais.e these extremely readable papers. 



OBSERVATIONS ON HABITS OF FUNGI IN 

 WESTERN PENNSYLVANIA. 



By David R. Sumstine. 



The classification and life-history of fungi has so oc- 

 cupied the attention of mycologists that their ecological re- 

 lations have been neglected. So many factors enter into the 

 study of these relations that general conclusions can be drawn 

 only after the most extended and exact field observations 

 have been made. Certain facts are apparent even to casual 

 observers, as for example a regular succession of genera and 

 species of fungi from the open to the more dense part of the 

 forest, the connection of certain fungus species with particu- 

 lar kinds of trees, altitude, involving different conditions that 

 influence the distribution of species, and so on; but more 

 definite observations are greatly needed as to seasonal habits, 

 relation to substratum, and associations than have yet been 

 recorded. In view of this the following notes on habits of 

 fungi taken by the writer on collecting trips in western Penn- 

 sylvania may be of sufficient value to place on record. 



It is noteworthy that many species of fungi endure very 

 low temperatures, and continue their development in the cold 

 winter weather of the northern states. Many of the Pyreno- 

 mycetes mature during the winter months in the latitude of 

 Pittsburg. CoIIybia vehitipes Curtis has been collected by 

 the writer in January, 1907, growing at the base of a small 

 decaying tree, where much of the time it was cov^ered with 

 snow, but developing sporophores of ordinary size. The 

 mycelium continued to grow during the winter, and a new 

 crop of sporophores appeared in March of the same year. 

 PU'iiroliis serotinus Schrader is found late in the season, 

 usually in October and November. The young plants are 

 often frozen hard during the night, but they grow to ma- 



