[Vol. 5 

 326 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



to 50 /i, originating from all parts of the setigerous layer al- 

 though chiefly from the dark, subhymenial zone; spores hya- 

 line, even, curved, 5-6x14-2 /x, as seen in preparation of 

 sections. 



Reflexed portion 3-7 mm. long, 10-15 mm. broad, often lat- 

 erally confluent; resupinate portions up to 3x30 cm. and 

 more. 



On dead limbs, usually of frondose species. Canada to 

 Mexico, Maine to the Pacific coast, Alaska to California. 

 Common in the north, rare further south. Throughout the 

 year. 



H, tahacina is the commonest species of its genus in the 

 northern United States and may be recognized by its reflexed 

 fructifications tobacco-colored with bright golden yellow 

 margin and intermediate layer, and by having the hymenium 

 deeply cracked in resupinate portions into radiating systems, 

 one system for about each centimeter of area. The specimen 

 under the name Stereum avellamum from Fries in Kew Herb, 

 is the old glabrous, somewhat reddish stage of H. tahacina; 

 this specimen has led to the transfer of Stereum avellanum 

 to Hymenochaete by British authors and Saccardo. An older 

 specimen of Thelephora avellana in Herb. Fries collected by 

 E. Fries at Femsjo is not distinct from Stereum glaucescens 

 but is unfortunately on coniferous wood, while T, avellana 

 was published as occurring on Corylus, a frequent substratum 

 in Europe for H. tahacina. The type of Thelephora im- 

 hricatula in Herb. Schweinitz is a mixture of Hymenochaete 

 tahacina, mounted on the right of the card, and of H, cor- 

 rugata, mounted at the left. Both these species are present 

 in the sample of T. imhricatula in Curtis Herb, but their order 

 has been reversed in mounting. The portion of the original 

 description pertaining to characters of reflexed portions of 

 the fructifications is obviously based upon the H. tahacina 

 portion of the type. Since Leveille's transfer of T. imhrica- 

 tula to Hymenochaete was probably based upon an authentic 

 specimen from Schweinitz in Museum of Paris Herb., in 1846, 

 this specimen will probably show whether any of H. corrugata 



