POLYPOKEAE OF SOUTH AFRICA. 253 



10. Plants terrestrial, deeply rooted, surface laccate, black 



in mature plant. P. nigrolucidus 35 



10. Plants epixylous, surface redbrown, laccate. P. lucidus 37 



1. Pileus sessile. 



11. Ilymenophore when moist separable from context as 



an elastic membrane. 



12. Mouths reddish-purple. P. dichrous 6 



12. Mouths white or flesh coloured. P. conchoides 7 

 11. Hymenophore not separable from context as above. 



13. Spores truncate. 



14. Spores hyaline. P. ochroleucus 8 



14. Spores coloured. P. lucid it* 37 

 13. Spores not truncate, hyaline. 



15. Edges of pore mouths soon breaking up into teeth. 



P. bi for mis 9 



15. Edges of pore mouths not breaking up into teeth as in 



preceding. 



16. Plants largely resupinate and witli small reflexed pilei. 



17. Pileus white, changing to reddish, mouths 6 or 7 to the 



millimetre. P. undatus 10 



17. Pileus not changing as above, soft and spongy, largely 

 resupinate, mouths large, 1 to 3 to the mm., shallow, 

 irregular; spores large. P. versiporus 11 



17. Pileus not changing, coriaceous, mouths 2 to 3 to 



the mm. P. pin si tit* 19 



16. Pileate portion usually more or less well developed. 



18. Surface with multicoloured zones. 



19. Context 1 mm. or less thick. 



2C. Surface velvety, tubes exceeding 1 mm. in length. 



P. versicolor 12 



20. Surface more strigose, less conspicuously zoned, tubes 



not exceeding 1 mm. in length. P. kirsutidus 13 



19. Context more than 1 mm. thick P. zonatus 14 



18. Surface sometimes zoned, but not marked with multi- 

 coloured zones. 



21. Surface with a conspicuous hairy covering. 



22. Context exceeding 1 mm. in thickness. 



23. Tubes less than 1 mm. long. P. velutinus 15 



23. Tubes more than 1 mm. long. 



24. Surface hirsute, pore mouths entire, persistently thick- 



walled, 3 to 4 to mm. P. hirsutus 16 



24. Surface hirtose-villose, pore mouths becoming thin 



walled, often dentate, 2 to 3 to mm. P. pubesceus 17 

 22. Context I mm. or less in thickness. 



25. Tubes more than 1 mm. long. 



26. Surface with a soft cottonv pubescence, pore mouths 



2 to 3 to the mm. P. hirtelhis 18 



25. Tubes less than 1 mm. long. 



27. Pileus thin, flexible, mouths irregular angular, shallow, 



2 to 3 to mm. P. pinsitiis 19 



