1915] 



OVERHOLTS — STUDIES IN THE POLYPORACEAE 705 



lapse when dry. This collapsing is due to the thinness of the 

 dissepiments — a character easily made out in transverse sec- 

 tions of the hymenium. The illustration (pi. 24 fig. 14) shows 

 the larger tubes of P. delectans. The spores of the two species 

 are practically the same, varying from ellipsoid to ovoid or 

 subglobose, and measuring 5-6x4-5 y.. They are frequently 



guttulate in both species. There are no cystidia in the 

 hymenium. 



P. galactinus. — This species is a fairly well-marked one and 

 only its distinguishing features will be pointed out here. It 

 was originally described by Berkeley from specimens collected 

 in Ohio by Lea. It is eastern in its range in the United States, 

 occurring from Maine to Missouri and probably no farther 

 south than West Virginia. There are but three common 

 plants in this section of Polyporus that possess characteristic 

 odors when fresh and growing. P. galactinus is one of them. 

 The odor is usually described as ' ' acid, ' ' but to the writer it 

 is a very pleasant and fragrant odor, but not persisting in 

 the dried plants. Characters are not wanting to separate this 

 species from the group just discussed in this section. The 

 pileus is strigose-pubescent, as shown in the illustration (pi. 24 

 fig. 15), the tubes are very small, and the spores are minute, 

 ellipsoid or subglobose, uninucleate, and measure 3-4 X 2-3 

 /i. From P. delectans and P. spumeus it may be separated by 

 the minute pores and the smaller spores. From P. fumidiceps 

 Atk. it differs in the decidedly pubescent pileus and larger size. 

 From P. caesius, which it resembles in its hairy covering, it 

 differs in its larger size and ellipsoid spores. There are no 

 cystidia. 



P. caesius. — This species has long been recognized as a well- 

 marked one, characterized by the villous-strigose pubescence 

 on the pileus, the bluish or grayish blue tint often present 

 on the hymenium, and the minute, cylindric, curved spores. 

 From P. galactinus it is separated by its small size and dif- 

 ferent spores; from P. chioneus and P. albellus by the pubes- 

 cent pileus; from P. lacteus by the more strigose pileus and 

 the unbranched hyphae of the context. 



