MICHIGAN ACADEMY OF SCIENCE. 63 



(aa) Flesh becoming black or brown in age or when bruised. 



(b) Gills subdistant to distant; flesh becoming reddish, then black where wounded. 



3. i?. nigricans Fr. 

 (bb) Gills close. 



(c) Odor disagreeable on drying; pileus whitish, becoming rusty-cchraceous. 



8. R. compacta Frost. 

 (cc) Pileus becoming smoky-brown. 



(d) Pileus viscid. , 5. R. subsordida Pk. 



(dd) Pileus dry. 4. R. sordida Pk. 



(ccc) Pileus or flesh red then black where bruieed; gills crowded. 



7. R densifolia Seer. 

 (AA) Gills mostly equal, the shorter ones, if any, scattered promiscuously; margin of pileus not in- 

 curved, or if so then striate, 

 (a) Gills much forked thruout; pileus firm and compact. 



(b) Gills crowded; pileus purplish, umber or greenish; flesh slowly acrid or astringent. 



20. R. variata Bann. 

 (bb) Gills subdistant; pileus vello wish-green to brownish-green; taste mild. 



21. i?. furcata Fr. 

 (aa) Gills forked only at the base, or forking not extensive, 

 (b) Spores white or whitish, 

 (c) Pileus white. 



(d) Taste acrid. 40. R. albidula Pk. 



(dd) Taste mild. 



(e) Pileus with a viscid pellicle, sometimes tinged yellowish. 



41. R. albida Pk. 

 (ee) Pileus with a dry pellicle sometimes tinged pink. 41. R. albella Pk. 

 (cc) Pileus some shade of green or dirty white. 



(dj Pileus with a continuous separable pellicle; gills subdistant; taste mild. 



24. R. aeruginea Fr. 

 (dd) Pileus areolate or cracked so as to form patches; gills rather close. 



(e) Pileus dry, with pulverulent or warty patches on disk, dark green when 



young," scarcely striate on margin. 18. R. virescens Fr. 



(ee) Pileus viscid, smooth on disk, mouldy-white to pale greenish-white, 

 margin striate. 19. R. crustosa Pk. 



(ccc) Pileus some shade of red, pink or purple, 

 (d) Taste mild. 



(e) Gills floccose-crenulate on edge; stem tinged red. 



4.3. R. purpurina Quel. & Schulis. 

 (ee) Edge of gills not crenulate. 



(f) Pileus firm and hard or compact, pellicle adnate or lacking. 



(g) Pileus rather large, bluish-purple, at times rosy to white, on disk 



22. R. cyanoxanfha Fr. 

 (gg) Pileus medium .size, dull lilac. 23. R. Hlacea Quel. 



(ggg) Pileus without blue or purple. 



(h) Cuticle thin, not reaching the margin; gills often stained 



yellowish-brown; stem white. 23. R. refca Fr. 



(hh) Surface of pileus minutely rimose-areolate: stem white or 

 rose color; spores straw-yellow. 10. R. lepida Fr. 

 (ff) Pileus thin, fragile or subfragile. 



(g) Pileus about an inch across, sometimes larger, clear pink. 



44. R. uncialis Pk. 

 (gg) Pileus dark violet-purple to purplish-red, silky-shining; medium 

 size; solitary. 45. R. sericeonilcns sp. nov. 



(ggg) Pileus bright* rosy-red with yellowish spots; rather large; m 

 troops. 42. R. subdepallens Pk. 



(dd) Taste acrid. 



(e) Pileus rather small. 



(f) Pileus rosy-red on margin, sordid olivaceous-brown on disk; gills 



subdi.stant; usually on moss. 36. R. fallax Cke. 



(ff) Pileus uniform rosy-red; gills close; in moist places. 



35. R. fragilis (Pers.) Fr. 

 (ee) Plants medium to large. 



(f) Taste tardily acrid. 34. R. rugulosa Pk. 



(ff) Taste verv acrid. 



(g) On sphagnum; large; in troops. 33. R. emetica. var. gregaria. 

 (gg) On debris of very rotten logs; scattered. 33. R. imehca I'r. 

 (cccc) Pileus some shade of brown, yellowish, etc. 

 (d) Odor aromatic, becoming foetid. 



(e) Margin of pileus even, then tubercular-striate, grayish-brown; pileus and 



stem with yellow pulverulent granules. 28. R. pulverulenta Pk. 



(ee) Pileus markedly striate on margin. 



(f) Pileus straw-yellow to dingy, margin at first incurved. 



32. R. foetcns Fr. 

 (ff) Pileus reddish-yellow; base of stem stained reddish-brown. 



31. R. foetentula Pk. 

 (dd) Odor not marked. 



(e) Taste mild; pileus and stem yellow, gills white. 



17. R. flairida Frost. 

 (ee) Taste mild. 



(f) Pileus dingy yellow, straw-yellow, or dirty yellowish-brown. 



(g) Pileus "covered with granules; no odor" 29. R. granulata Pk. 

 (gg) Pileus without granules; flesh ashy under cuticle; margin 

 strongly striate. 30. R. pectinatoides Pk. 



(eee) Taste acrid; pileus gray, grayish-brown, olive brown or umber. 



(f) Stem becoming cinereous with age. 27. R. con.-iobrina Fr. 



(ff) Stem not becoming ashy. 26. R. sororia Fr. 



