28 



Mycologia 



6. Psathyrella Stevensonii sp. nov. 



Pileus conic or campanulate to convex and finally expanding, 

 more or less umbonate, gregarious to subcespitose, 4-7 cm. broad ; 

 surface hygrophanous, distinctly sulcate-striate to the disk, brown 

 or chestnut at first, fading to cinereous or isabelline, covered 

 with prominent, white, floccose scales when young, at length 

 glabrous ; margin appressed when young, splitting with age ; con- 

 text with mild flavor and pungent, rather pleasant odor ; lamellae 

 adnexed, crowded, rather narrow, pallid to' almost black, not 

 deliquescing; spores ellipsoid, smooth, opaque, dark-chestnut 

 under the microscope, black in mass, about 11 X 6/x; stipe taper- 

 ing upward, white, shining, hollow, glabrous or whitish-floccose, 

 7-10 cm. long, 3-8 mm. thick ; veil white, scanty, soon evanescent. 



Type collected in garden soil at Rio Piedras, Porto Rico, June, 

 1915, /. A. Stevenson 2785 (herb. N. Y. Bot. Gard.). Also col- 

 lected in chip dirt in a yard at Herradura, Cuba, October 10, 

 1906, F. S. Earle 546, and in a door-yard at the same place, No- 

 vember 3, 1906, F. S. Earle 556*. This plant is rather large and 

 the stipe rather thick for Psathyrella, but it cannot go' into Co- 

 prinus because the lamellae do not deliquesce. This character 

 was carefully noted by Stevenson. At first sight, one is reminded 

 of Coprinus micaceus, which is smaller, more clustered, and has 

 much smaller spores. Cooke's figure of Psathyrella arata repre- 

 sents the form of the plant fairly well. 



Doubtful Species 



Psathyrella hiascens (Fries) Quel. Champ. Jura Vosg. 123. 

 1872. (Agaricus hiascens Fries, Syst. Myc. 1: 303. 1821.) 

 Described from specimens collected on the ground in humid 

 woods in Europe and reported by Peck from New York. Speci- 

 mens collected in Costa Rica by Oersted were referred to this 

 species by Fries, but it is very probable that they are distinct. 

 Oersted's figures represent a densely cespitose plant with hemi- 

 spheric pileus, totally different . from the campanulate, umbonate 

 pileus shown in Bulliard's and Cooke's figures. Unfortunately, 

 there are no specimens extant from which spores might be ob- 

 tained. This species was also reported from Dominica by Miss 

 A. L. Smith, but I have not seen the specimens. 



