1915] 



OVERHOLTS — STUDIES IN THE POLYPORACEAE 687 



fuscoviolaceus as incrusted at the apex in the same manner as 

 shown in the accompanying illustration of P. abietinus. I 

 have also found this condition to be predominant in the lamel- 

 late form of our species. 



The following comparative synopsis of the two species dis- 

 cussed in this section is appended here : 



1. Polyporus abietinus Dicks, ex. Fries. 



Plate 23, figs. 1, 2. 



Pileus coriaceous, sessile or effused-reflexed, 0.5-5 X 0.5-5 

 X 0.1-0.2 cm., white, cinereous, or blackish with age, villous, 

 zonate; context not more than 1 mm. thick; tubes not more 

 than 3 mm. long, the mouths white, bay, or violaceous, averag- 

 ing 2-3 to a mm. in poroid forms, but sometimes entirely 

 lamellate; spores cylindric or allantoid, hyaline, 5-7 X 1.5- 

 2.5 n; cystidia present or inconspicuous, hyaline, rarely in- 

 crusted at the apex, 3-6 \i in diameter, projecting 5-15 /x; 

 hyphae of context hyaline, 3-4 y, in diameter. 



On wood of coniferous trees, especially of Pinus. 



Illustrations : Dicks. PI. Crypt. Brit. 3 : pi. 9. f. 9.—F\. Dan. 

 pi. 1298, 2079. f. 2.— GilL Champ. Fr. pi. 463.— Swant. Brit. 



Fung. pi. 33. f. 2-3. 



Specimens examined: Barth. Fung. Col. 3108.— Cooke, 

 Brit. Fung. 512, 605.— Thuem. Myc. Univ. 6, 706.— Ell. N. Am. 

 Fung. 8.— Ell. & Ev. Fung. Col. 303.— Krieg. Fung. Sax. 1205. 



Rab.-Wint. Fung. Eur. 3235 (as Irpex fuscoviolaceus) 



Rav. Fung. Am. 422 ; Fung. Car. I, 12.— Shear, N. Y. Fung 



307.— Mo. Bot. Gard. Herb. 4726, 4727, 4728 (Newfoundland) 



3854, 4213 (New York), 4214 (Labrador), 4220 (Alabama) 



4074 (Colorado). — Burt Herb, (collections from Vermont and 

 Washington) .— Overholts Herb. 2001 (Colorado), 2465 (Penn- 

 sylvania), 2472 (Maine). 



2. Polyporus pargamenus Fries. Plate 23, fig. 9. 



Pileus coriaceous, sessile, often narrowed at the base 



1-7 X 1-7 X 0.1-0.4 cm., whitish, cinereous, or brownish with 

 age, villous or velvety-pubescent, zonate; context less than 

 1 mm. thick; tubes not more than 3 mm. long, the mouths 

 white, bay, or violaceous, averaging 2-3 to a mm. in poroid 



