426 MurrRILL: POLYPORACEAE oF NortTH AMERICA 
listed and described is Scutiger tuberosus Paul., later changed to 
Polyporus asperellus by Leveillé, a well-known European species 
belonging to the section Ovni of Fries and to the genus Polyporus 
of Karsten and Caloporus of Quélet. Albatrellus of S. F. Gray, 
another synonym of Scutiger, 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 Scutiger 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. Polyporus 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 Polyporus frondosus 
under the genus Grifo/a. A somewhat older stage of P. poripes 
was described by Berkeley and Ravenel in 1872 as P. flavovirens. 
Synopsis of the North American species 
1. Surface of pileus uneven, squamose or rugose. a 
Surface of pileus smooth, tomentose or glabrous, * 
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 9 X 6/4. - 
1. S. Eilist. 
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. 5. relip 6 
Tubes small, 0.5 mm. in diameter, polygonal, decurrent, white, pileus reddish- 
brown, rugose, stipe central, not reticulate. 3. 5. denen 
4. Pileus light-colored, white, red or blue. z 
Pileus dark-colored, gray or brown. - 
5. Pileus white, context white, tubes irregular, dissepiments thin, white, plants small, 
growing upon grass roots, stipe short, dark-brown. 4. S. eryplopus: 
Pileus red, glabrous, stipe short, concolorous, context rose-colored, tubes short, 
small, 1-2 0.2 mm., decurrent, orange-colored, spores ovoid, hyaline, 
4X 5-6. 5, & laeticolor. 
Pileus blue when fresh, changing to brown on drying. & 
