THE AGARICACEAE OP MICHIGAN 



(c) Plant rather stout; basidia 4-spored; volva large. 641. A. 



verna Pr. 

 (cc) Plant slender; basidia 2-spored; otherwise like preceding. 

 642. A. bisporigera Atk. 

 (aaaa) Pileus brown, umber, gray, drab or shades of these. 

 ' (b) Base of stem cylindrical, not bulbous; pileus pale brown to 

 umber. 646. A. spreta Pk. 

 (bb) Base of stem bulbous, bulb rounded, 

 (c) Pileus viscid, pale smoky olive, umber, or smoky white, often 

 with shreds of veil on top; annulus apical, white. 640. A. 

 phalloides Pr. 

 (cc) Pileus scarcely viscid or dry; stem slender. 



(d) Spores elliptical, 11-13 x 7-9 micr.; pileus brown or grayish- 

 brown; disk with white patch-like scales. 648. A. recu- 

 tita Fr. 

 (dd) Spores globose. 



(e) Pileus scarcely viscid, fuscous to pale brown, glabrous; 

 annulus distant, brownish; bulb rather small. 644. A. 

 porphyria Fr. 

 (ee) Pileus with numerous ash-colored appressed scales; 

 ash-colored pulverulence on stem. 647. .1. tomentella 

 Kromb. 

 (AA) Base of stem or bulb without a cup-like, free-margined volva. 

 (a) Pileus orange, yellow or straw colored, 

 (b) Margin of pileus markedly tubercular-striate, yellowish to straw 

 color; annulus evanescent; volva usually evanescent or a few 

 •scales on bulb. 656. A. russuloides Pk. 

 (bb) Margin even or only slightly striate; pileus orange to bright 

 yellow; annulus persistent, 

 (c) Flesh of stem changing to reddish when bruised or in age. 



658. A. flavorubescens Atk. 

 (cc) Flesh not reddish, 

 (d) Pileus large, more than 7 cm. broad; stem stout, provided 

 with prominent, concentric scales or rings on or above bulb. 

 650. A. muscaria Fr. 

 (dd) Pileus less than 7 cm. broad, 

 (e) Bulb with an adherent, inrolled, collar-like ring on its 

 upper margin; spores spherical. 651. A. frostiana Pk. 

 (ee) Bulb and pileus with a few, flocculent masses of the fri- 

 able, yellow volva; spores oval; common. 659. A. flavo- 

 conia Atk. 

 (aa) Pileus not yellow nor yellowish. 



(b) Odor strong of chlorine or chloride of lime; stem bulbous- 

 napiform, more or less deeply rooting; plant entirely white and 

 very densely floccose-scaly. 655. A. chlorinosma Pk. 

 (bb) Odor not penetrating like chlorine. 



(c) Base of stem more or less deeply rooting below an enlarged 

 or concentrically furrowed bulb, 

 (d) Pileus white to grayish; plants large and stout, densely 

 floccose scaly. 654. A. solitaria Fr. A. strobiliformis Fr. 

 (dd) Pileus or its scales grayish-brown to umber-brown; plants 

 slender, covered with a loose pulverulence; spores 8-12 x 

 4-6 micr. A. cinereoconia Atk. 

 (cc) Base of stem rounded, or at most short conical below, 

 (d) Flesh of stem or of whole plant turning to reddish where 

 bruised or in age. 

 (e) Pileus decorated with yellow powdery masses; flesh chang- 

 ing to red only toward base of stem. 658. A. flavoru- 

 bescens Atk. 

 (ee) Pileus decorated with grayish or reddish-stained, floccose 

 warts; whole plant becoming reddish, never yellow. 657. 

 A. mbescens Fr. 



