k ia fa 
^ ME ENTA E 1 
1920] 
BURT—THELEPHORACEAE OF NORTH AMERICA. XII 125 
upper side villose-tomentose, light buff to cartridge-buff, the 
margin entire; hymenium even, glabrous, light purple-drab to 
dark vinaceous-drab; in structure about 500-800 u thick ex- 
cluding the tomentum, with the intermediate layer more loosely 
arranged on its under side in the 
subhymenial region and contain- ps EE 
ing pyriform, orsubglobose, vesic- tl | J JJ n TT 
ular organs 15-30X12-25 y; no UMA 
cystidia; spores hyaline, even, IAS Roe 
flattened on one side, 5-7 X 21-3 y. P, eei. ut CN 
Fructifications with resupinate LEE n 
portion about 1-2 cm. in diam- 
eter; reflexed portion 5-20 mm. Fig. 13. S. purpureum. Section 
broad, and sometimes crisped e: E oe pre 
) ular bodies X 665. From authentic 
or lobed with lobes 5 mm. in specimen. 
diameter. 
On dead stumps and logs of Populus, Betula, and other fron- 
dose species. Newfoundland to Delaware and westward to 
British Columbia and Oregon, also in Uruguay and in Europe. 
June to April. Common but not ranging into torrid regions. 
S. purpureum is usually recognized by its buff, tomentose 
pileus, purplish hymenium which does not bleed when wounded, 
and occurrence on poplar. Sectional preparations show charac- 
teristic vesicular organs in the subhymenial region, such as 
are present in the closely related S. rugosiusculum, but no hair- 
like cystidia in the hymenium, by the absence of which S. pur- 
pureum is distinguished from the latter. 
The authentic specimen of S. vorticosum in Herb. Fries at 
Upsala is 2-3X13 cm., narrowly reflexed, with dark purplish 
hymenium, and with the usual microscopic structure and spores 
of S. purpureum. 
Specimens examined: 
Exsiccati: Bartholomew, Fungi Col., 3489; Berkeley, Brit. 
Fungi, 147; Cooke, Fungi Brit., 12; Ell. & Ev., N. Am. 
Fungi, 2018, 2601; Klotzsch, Fungi Germ., 50; Krieger, 
Fungi Sax., 1852; Rabenhorst, Herb. Myc., 504; Romell, 
Fungi Scand. Exs., 27; Shear, N. Y. Fungi, 311. 
Europe: authentic specimen of Thelephora purpurea from Per- 
soon (in Herb. Hooker in Kew Herb.). 
