642 Murrill: Polyporaceae of North America 



8. Tubes small, 5 to a mm., and perfectly regular and entire. 4. C. eciypus. 



Tubes twice as large, often irregular from splitting ; glabrous zones late in appear- 

 ing and sometimes absent. 5* ^- pxibeuens, 

 g. Sporophore semiresupinate, shortly reflexed, tubes r cm. or more in length. 



6. C subluteus, 



Sporophore wholly pileate, tubes less than 1 cm. in length. 7. C. Sartweliii. 



10. Plants white or very light-colored. 



Plants more or less gray or brown. 



11, Hymenium lilac- colored, often faded in herbarium specimens. 8. C brachypus. 



12. 



II. 

 16. 



Hymenium white or yellowish. 



12, Margin of pileus entire or lobed, not becoming fimbriate or lacerate. 13. 

 Margin of pileus very thin, becoming fimbriate or lacerate at maturity. 14. 



13. Sporophore extremely thin and very flexible, with only one or two, if any, shining 



9. C haedinus. 



zones. 



Sporophore thicker and quite rigid, with several shining zones. 10, C ilicincola. 

 14. Tubes large, 2-3 to a mm., margin fimbriate. II. C Drummondii, 



Tubes only half as large, margin lacerate, 

 15. Sporophore dimidiate. 



15- 



12. C, fuevibranaceiis. 



Sporophore elongated, spatulate. 13. C. Flabellnfu. 



16. Pileus marked with brown and black zones ; temperate species. 14. C. planellus. 

 Pileus marked with brown and tawny zones ; tropical species. 17- 



17. Tubes 5 to a mm.; pileus 5 cm, broad, pale tawny, with darker brown zones; 



velvety zones present in young stages seem soon to disappear. 



15. C*. arvienicolor. 

 Tubes 3 to a mm.; pileus 3 cm. broad, umbrinous-cinereous, subzonate. 



16. C. sobrius, 

 iS. Pileus 0.5 cm. or more in thickness and several centimeters wide. 19. 



Pileus much thinner. 



20 



19. Dissepiments obtuse, margin broadly sterile below. 17. C. nigromarginatus. 



Dissepiments acute, margin but slightly sterile below. 18. C Suilivautii, 



20. Hymenium becoming wholly or partly fuscous, tubes broad and very shallow. 2X. 

 Hymenium not becoming fuscous. , 22. 



21. Tubes regular in shape and size ; plant tropical. 19. C. pinsitus. 

 Tubes irregular both in shape and size ; plant confined to the southern United 



States. 

 22. Tubes large, 2-3 to a mm. 



Tubes small, 5 to a mm. 



23- Edges of tubes entire. 



Edges of tubes thin, serrate. 

 24. Plants large, 6-20 cm. wide and about I cm. in thickness. 24. C biformis. 



20. C, sericeohirsutus, 



23. 

 21, C a rent color. 

 22. C hii'iellus, 

 2^, C fener. 



Plants much smaller and always very thin. 



25- 



25. Surface ashy-white, vlllose ; plant confined to coniferous wood. 25. C, abietinus. 

 Surface wood-colored, tomentose ; plant found on both deciduous and coniferous 



26. (7. pargamenus. 



wood. 



• I. CoRioLUS VERSICOLOR (L.) Quel 



Boletus versicolor L. Sp. PI. 1176, 1753. 



Poly poms versicolor Fr. Syst. Myc. i : 368. 182 1 



