424 MurRILL: POLYPORACEAE OF NORTH AMERICA 
mouths of the pores and wholly or partly concealing them from 
view, generally opening beneath by a small aperture; pores not 
stratose, the dissepiments thickened at the mouths and there dif- 
ferently colored.” 
In raising this section to generic rank, Shear cites Peck’s de- 
scription and the description of the single species contained in the 
section following, with a brief discussion of varieties and several 
additional collections from new localities. 
CryPTOPORUS VOLVATUS (Peck) Shear 
Polyporus volvatus Peck, Rep. N. Y. State Mus. 27: 98. 1877. 
Polyporus obvolutus Berk. & Cooke, Grevillea, '7: 1. 1878. 
Fomes volvatus Cooke, Grevillea, 13: 119. 1884. 
Cryptoporus volvatus Shear, Bull. Torrey Club, 29: 450. 1902. 
This peculiar plant was described from specimens collected on 
Abies nigra. It is also found rarely on Adies balsamea, but seems 
to prefer species of pine, upon which it is quite common. I have 
seen dead trunks of Pinus rigida filled with the mycelium, the 
fruit bodies emerging through holes made by beetles. It is pos- 
sible that the specimens found on charred wood in the West are 
larger than our Eastern plants because no effort is required to 
reach the surface through a heavy layer of cortex. Torrey’s stip- 
itate Western form figured by Gerard is duplicated at times in the 
East when the plant grows on the top of alog, Henning’s variety 
felix from California is fully described by Peck and differs in no 
way from the type, which had not been seen when the variety was 
described. Peck’s varieties obvo/utus and Torreyi seem hardly 
worthy of separation. P. evolvens Berk. & Cooke, Herb. Berk. 
1879 from California, fastened to a sheet of P. evolutus B. & C» 
is only P. volvatus and is very distinct from P. evolutus. 
Exsicc.: California, Harkness, Torrey, McClatchie ; Colorado, 
Crandall, Shear & Bessey ; Oregon, Shear, Carpenter ; West Vir- 
ginia, Nuttall; New York, Murrill; Michigan, Roddins ; British 
Columbia, Macoun ; Delaware, Commons; District of Columbia, 
Shear, Hicks. 
Piprororus Karst. Rev. Myc. 3: 17. 1881 
This genus was originally established upon a single species, 
Polyporus betulinus (Bull.) Fr., and: has since remained monotyp!¢ 
