100 MUKRILL : POLYPORACEAE OF NORTH AMERICA 



i. Favolus tenuis (Hook.) 



Boletus reticulatus Hook, in Kunth, Synopsis I : (9). 1822. Not 



B. reticulatus Schaeff. 

 Boletus tenuis Hook, in Kunth, Synopsis 1 : (10). 1822. 

 Polyporus polygrammus Mont. Ann. Sci. Nat. II. Bot. 8 : 365. 



1837- 

 Hexagona tenuis Fr. Epicr. 498. 1838. 



Hexagona polygrammaYx. Epicr. 497. 1838. — Mont. PI. Cell. 



Cuba 379. pi. 14. f. 3. 1842. 

 Hexagona favoloides Peck, Bull. Torrey Club 10: 73. 1883. 



This species is found in the Linnaean herbarium marked 

 Boletus favus, but not by Linnaeus nor with his sanction. It was 

 first described by Hooker from plants collected in the Andes 

 between Popayan and Almaguer by Humboldt, under the name of 

 Boletus reticulatus. Following this species on the next page is 

 Boletus tenuis, described as differing from the preceding in its 

 paler, smooth, dimidiate pileus and empty pores. According to 

 Klotzsch, Boletus reticulatus is only a monstrous form of Boletus 

 tenuis with the pores spongy-stuffed and the pileus orbicular, fixed 

 at the center and more than usually reticulate-rugose on the 

 surface. This view is strengthened by the fact, which Hooker 

 states, that the two species were found growing together. 



In reviewing Klotzsch's work in 1839, Berkeley lists Boletus 

 reticulatus as synonymous with Boletus tenuis and enlarges 

 Hooker's description from the original specimens, explaining that 

 the monstrous form in question was caused by the accidental 

 reversal of the log or branch upon which it grew and that the 

 spongy-stuffed pores were due to the beginning of a new pileus, 

 while the abnormal reticulations on the surface were caused by a 

 new hymenium beginning to form on the old pileus. This leaves 

 practically no doubt as to the identity of the two species ; but 

 since the first name is antedated by one of Schaeffer's, Boletus 

 tenuis would hold for our plants in spite of the doubt. 



The Cuban plant, finely described and figured by Montague, 

 appears in the figure to have larger pores than plants from else- 

 where, but the type collections do not indicate that it is specifically 

 different. 



