80 



Mycologia 



pointed out by Earle. The separation of A. muscaria and related 

 species into the genus V enenarius is hardly practical, since the 

 form of the basal volva is not constant in either of the two genera 

 thus separated. 



Leucomyces mexicanus sp. nov. 



Pileus convex, regular, 5 cm. broad ; surface milk-white, smooth, 

 dry, with satiny luster, adorned with patches of the membranous 

 volva, which are 2-3 mm. broad, thin, white, separable ; margin 

 thin, entire, concolorous ; context thin, white, odor distinct, pleas- 

 ant ; lamellae white, remote from the stem, arcuate, narrow, 

 crowded ; spores oblong, smooth, hyaline, 4-5 X 2 /x ; stipe cylin- 

 dric, equal, white, hollow, glabrous, 4.5 cm. long, 4 mm. thick, 

 not swollen at the base ; annulus superior, membranous, ample, 

 white, movable; volva white, circumscissile, the basal portion 

 small, collapsed, and scarcely noticeable. 



Type collected on rich earth in a moist virgin forest near Mot- 

 zorongo, Mexico, 400 meters, January 15, 1910, W. A. Murrill 

 1067. 



This species resembles Lepiota more than it does most species 

 of Leucomyces, but it has a distinct volva and the pileus shows 

 separable volval patches. The odor is pleasant, suggesting Tra- 

 metes suave olens, though not so distinct. 



2. Vaginata (Nees) S. F. Gray, Nat. Arr. Brit. PI. 1: 601. 



1821 



Ammitopsis Roze, Bull. Soc. Bot. Fr. 23 : 50. 1876. 



This genus differs from Leucomyces chiefly in lacking a veil, 

 although both genera have the sheath, or volva, at the base of 

 the stipe. 



Vaginata vaginata (Bull.) 

 Agaricus vaginatus Bull. Herb. Fr. pi. 98. 1782. 



This species, so abundant in temperate regions, probably occurs 

 sparingly in the northern Bahamas and in the high mountains of 

 our tropics. The Bahamian material, collected by Mr. Nash, is 

 pressed flat and is without notes, except that the color was white 

 and no ring was observed. Two specimens collected by myself 

 at Chester Vale, Jamaica (No. 351), at an elevation of over 3,000 

 ft., agree very well with the small, murinous, temperate form of 

 this species, but the base of the stipe and volva were, unfortu- 



