426 MuRRiLL : Polyporaceae of North America 



listed and described is Scutigcr tiiberosns Paul, later changed to 

 Polyporiis asperdliis by Leveille, a well-known European species 

 belonging to the section Ovini of Fries and to the genus Polyporiis 

 of Karsten and Caloporus of Quelet. Albatrelhis of S. F. Gray, 

 another synonym of Scntiger, antedates the two last mentioned by 

 more than half a century. Plants belonging to this genus are 

 central-stemmed, fleshy-tough and terrestrial with white flesh, 

 rounded pores and smooth, hyaline spores. Some of the members 

 of this group approach the closely related genus Boletus, but are 

 firmer, tougher and more lasting. 



As to distribution, the species of Scntiger are, in general, limited 

 to rather small areas ; few of them are common, some are rare and 

 local, and, so far as known, European and American species are 

 entirely distinct. The indications are that the plants lack vigor 

 and are easily affected by soil, climate and other environmental 

 conditions. Polyportis poripes Fr. was placed in this group before 

 the plant was fully known. Mature specimens show that it 

 belongs rather with multiplex forms such as Polyporiis frondosus 

 under the genus Grifola. A somewhat older stage of P. poripes 

 was described by Berkeley and Ravenel in 1872 as P. flavovirens. 



Synopsis of tbe North American Species 



1. Surface of pileus uneven, squamose or rugose. 2. 

 Surface of pileus smooth, tomentose or glabrous. 4- 



2. Pileus sulfur-yellow, pleuropus, surface ornamented with imbricated floccose wart- 



like scales, context white or yellowish, tubes small, angular, decurrent, white, 

 becoming greenish when wounded, yellowish when dry, spores 9X6//. 



I. S. Ellisii. 



Pileus brown. 3- 



3. Tubes large, 1.5 mm. or more in diameter, hexagonal, surface of pileus smoky- 



brown ornamented with darker imbricated tufts of appressed hairs, context 

 white, stipe excentric, its entire surface reticulate. 2. S. retipes. 



Tubes small, 0.5 mm. in diameter, polygonal, decurrent, white, pileus reddish- 

 brown, rugose, stipe central, not reticulate. 3. S. dectirrens. 



4. Pileus light-colored, white, red or blue. 5- 

 Pileus dark-colored, gray or brown. 7- 



5. Pileus white, context white, tubes irregular, dissepiments thin, white, plants small, 



growing upon grass roots, stipe short, dark-brown. 4. S. cryptoptis. 



Pileus red, glabrous, stipe short, concolorous, context rose-colored, tubes short, 

 small, 1-2X0.2 mm., decurrent, orange-colored, spores ovoid, hyaline, 

 4X5-6/i. 5- S. laeticolor. 



Pileus blue when fresh, changing to brown on drying. 6. 



