326 MurRILL: POLYPORACEAE OF NORTH AMERICA 
some of them vary to centrally stipitate forms and a few species are 
regularly mesopous. All grow upon dead wood and agree closely 
in habit and host plants. One American species is common also 
in Europe, the others are limited to either temperate or to tropical 
regions of America. Many of them are very imperfectly known. 
Synopsis of the North American species 
1. Tubes unequally hexagonal, the radial walls longer. 2. 
Tubes equally hexagonal 15. 
2. Pileus white or nearly so. 3: 
Pileus purple or brown. 12. 
3. Surface ef Ripe glabrous or minutely hairy or fibrillose, not distinctly hispid or 
tom 
Serta a aiken distinctly hispid or tomentose. 9. 
4. Pileus reniform at maturity, stipe usually much reduced ; species not tropical. 5. 
Pileus flabelliform, stipe usually very distinct, equalling the pileus at times in 
ength ; species tropical 6. 
5. Tubes large, surface of Peas decorated with imbricated reddish-brown fibrils, 
which disappear with age. 1. H, alveolaris. 
Tubes much smaller, Pe mouths rarely over I mm. long and 0.5 mm. broad, 
surface of pileus glabrous. 2. H. micropora. 
6, Tubes of medium size ; pileus large and tough, margin not ciliate. 3. . daedalea. 
Tubes large, mouths 1-2 mm. broad and 3-5 mm. long. : 
ye ret: vise dents and fissured at maturity. ya re Wilsonii. 
Margin 8. 
8. Pileus small, 5 cm. in breadth. ae: A hispidula. 
Pileus large, 10 cm. in breadth, 6. H. princeps. 
9. Surface not tessellated. 10. 
Surface tessellat II. 
10, Tubes large, the mouths 1 x 4 mm., becoming radially confluent and gill-like ; con- 
i. 
text only partially translucent. 7. H. fragilis. 
Tubes small, the mouths about half as large as in the preceding and not becoming 
confluent ; context thinner, wholly translucent. 8. H. floridana. 
11. Pileus small, thin and fragile, the surface minutely checkered. 9. 4. tessellatula. 
ta. 
Pileus large, thick and firm, the surface coarsely checkered. 10. H. caperata 
12. Pileus purple or purplish-brown, stipe lateral or excentric. 13. 
Pileus brown, fe distinctly central. i+ 
13. Tubes merulio 11. H, brunneola. 
Tubes of eeu length, 12. H. purpurascens. 
14. Margin entire. I 3. H. portoricensts. 
Margin ciliate. 14. A. hondurensts. 
