270 



Mycologia 



Pileus grayish-black. 



Surface deeply radiate-sulcate. 



11. P. Clementsii. 



12. P. angusticeps. 



Surface smooth, not sulcate. 



Pileus some shade of brown, yellowish-brown, or 



reddish-brown. 



Stipe i—2 mm. thick. 

 Stipe white. 

 Stipe reddish-fulvous. 



13. P. atomata. 



14. P. petasiformis. 



Stipe 2-4 mm. thick. 

 Stipe 5-8 cm. long. 



Lamellae crowded. 

 Lamellae distant. 

 Stipe 10-13 cm. long. 



15. P. odorata. 



16. P. distantifolia. 



17. P. graciloides. 



i. Psathyrella minutula (Schaeff.) Murrill, Mycologia 10: 



26. 1918 



Agaricus minutulus Schaeff. Fung. Bavar. Ind. 72. 1774. 

 Agaricus disseminatus Pers. Syn. Fung. 403. 1801. 

 Psathyrella disseminata Quel. Champ. Jura Vosg. 123. 1872. 



Pileus membranaceous, ovoid-campanulate, densely gregarious 

 or cespitose, 6-10 mm. broad; surface minutely scaly, becoming 

 smooth, whitish, gray, or grayish-brown, often buff on the umbo, 

 margin sulcate-plicate ; context very thin, with mild taste and no 

 odor ; lamellae adnate, broad, subdistant, ventricose, white to gray, 

 then black; spores ellipsoid, tapering at both ends, smooth, dark- 

 purplish-brown in mass, chestnut-bay under the microscope, 8-9 x 

 4 stipe furfuraceous to glabrous, white or yellowish to cinereous, 

 very slender, becoming hollow, often curved, about 2.5 cm. long 

 and 1 mm. thick. 



Type locality : Bavaria. 



Habitat : On decayed wood and moist earth containing organic 

 matter. 



Distribution : Cosmopolitan. 



Illustrations: Atk. Stud. Am. Fungi, /. ^p;-Boud. Ic. Myc. 

 pi. 140; Gill. Champ. Fr. pi. 141 {586) ; Hard, Mushr. /. 280; 

 Mycologia 6: pi. 132, f. 1; Pat. Tab. Fung. /. 351; Schaeff. Fung. 

 Bavar. pi. 308; Bull. U. S. Dept. Agr. 175: pi. 2$, f. 2. 



This very attractive little species was first described from Ba- 

 varia and accurately figured in color by Schaeffer. The synonymy 

 is considerably complicated but it seems quite certain that the 

 specific name under which the plant is best known has been in use 



