SPORES HYALINE. SETAE PRESENT. 



SECTION 70. CONTEXT BROWN. SETAE PRESENT. SPORES HYALINE. 

 A. Context Light Brown. 



FOMES POMACEUS (Fig. 588). Pileus half unguliform, but 

 usually more inclined to take a subresupinate form with the pileus 

 imperfectly developed. Surface at first fulvous, tomentose on the 

 margin, later cinereous, after wintering turns dark, but not black as 

 Fomes igniarius. Context fulvous brown (Amber brown), interme- 

 diate between the color of context of Fomes igniarius and Fomes 

 robustus. Pores minute, round, annual layers 5-6 mm. Setae usually 

 abundant, with thickened base, projecting 12-16 mic. Spores globose, 

 hyaline, 5-6 mic. 



Fig. 588. 



Fomes pomaceus. 



Komes pomaceus is a frequent plant in Europe, usually on the plum trees 

 (Prunus). In fact, in England it is a distinctive disease of the plum. It occurs in 

 Europe also on cherry and other allied cultivated trees, but never, I believe, except 

 on trees of the Rosaceous family. With us in the United States I only know it on 

 wild species of Prunus. I have never noted it on cultivated plums. 



Persoon had a clear idea of Fomes pomaceus, as is evident from his specimen 

 and writings, and he seems to have been the only one who had until recent years. 

 Fries held it as a variety of Fomes igniarius, and his description of igniarius was 

 drawn partially from this plant. Schroeter confused it with Fomes igniarius. Berke- 

 ley always referred it to Fomes igniarius, and those who followed Berkeley in England 

 have apparently never learned the difference. Quelet got it right. Bresadola dis- 

 covered that it was Fomes fulvus of Scopoli, being one of six different men who 

 have interpreted Scopoli's vague writings, each one with a different species. Murrill 

 copied Bresadola. It was the basis of Fomes supinus (sic) in Morgan's work. 



ILLUSTRATIONS. If it has been illustrated, it has been under the name of igniarius or tulvus 

 probably. I have not bothered to look them up. 



SPECIMENS. Many from Europe, mostly on plum trees. Many from the United States on 

 wild plum. Foreign, Madeira, Carlos A. de Menezes, exactly as in Europe. Australia, Edmund 

 Jarvis, specimen doubtful, cfr. Letter 37. 



