206 



Mycologia 



pi 129 (572, 573) ; Hard, Mushr. /. 248, 24$; Hussey, 111. Brit. 

 Myc. 1 : pi go; Mcllv. Am. Fungi, pi gi, /. 4, 5; Murrill, Ed. 

 Pois. Mushr. /. 11; Mycologia 1 : pi 3, f. 1; pi 15, f. 4; N. Marsh. 

 Mushr. Book, pi 18, f. 1; Palmer, Mushr. Am. pi 1; Richon & 

 Roze, Atl. Champ, pi 14, f. 1-15; Ricken, Blatterp. Deutschl. 

 pi. 61, f. 6; Sow. 'Engl. Fungi, pi 305. 



I have found the common edible mushroom wherever I have 

 traveled, whether in northern or southern Europe, tropical Amer- 

 ica, or on the Pacific coast. About New York City it usually 

 appears in late summer and early autumn. There are many va- 

 rieties, which need not be discussed here. The literature of the 

 species is extensive. 



9. Agaricus variabilis Peck in Mcllv. Am. Fungi 346. 1900; 

 not A. variabilis Batsch, 1783 



Pileus ovoid to campanulate, becoming irregularly convex or 

 nearly plane, subumbonate, densely cespitose, 10-15 cm. broad; 

 surface smooth, minutely fibrillose or slightly floccose, pure-white, 

 tinged with lilac in young plants and with yellow when older; 

 margin not striate, but sometimes split; context very thin toward 

 the margin, white, unchanging, with a strong almond-like taste and 

 a slight odor of musk, edible, never attacked by larvae; lamellae 

 free, crowded, ventricose, rather narrow, pure-white when young, 

 becoming dark-umbrinous, without the usual purplish tint; spores 

 dark-umber-brown, without a shade of purple ; stipe equal, not 

 bulbous, white, silky, smooth above the annulus, minutely scurfy 

 below, 5-8 cm. long, nearly 1 cm. thick ; annulus ample, white, 

 mottled with yellow scales on the under side, persistent, fixed above 

 the middle of the stipe. 



Type locality : Mt. Gretna, Pennsylvania. 



Habitat : In an old roofless stable. 



Distribution : Known only from the type locality. 



Illustration : Mcllv. Am. Fungi, pi pi, f. 1. 



According to Mcllvaine, who discovered the species, it grew in 

 large quantities in an old stable from September until after frost. 

 I have not seen the types. It is said to differ from A. subrufescens 

 in being snow-white when young and tinged with light-lilac rather 

 than with reddish-brown. If it is really a good species, a new 

 name must be found for it. 



