LEUCOSPORI. 135 



when moist, shining when dry, never pruinose or when dry Mycena. 

 rugulose. Stem 5-7.5 cent. (2-3 in.) long, slightly firm, rigid, 

 but like the whole plant fragile, equal, slippery (not viscous) when 

 moist, shining when dry, smooth, villous at the base, normally 

 yellow, but often cinereous. Gills adnate, somewhat distant, con- 

 nected by veins or distinct, slightly ventricose, glaucous-white or 

 dark cinereous and whitish at the edge, sometimes becoming 

 cinereous-yellow. 



Varying very much in stature. It is readily distinguished by its strong alka- 

 line odour, and by its pileus and stem not having a viscid pellicle, from A. 

 epipterygius, with which it so agrees in the colours, which vary in each in an 

 analogous manner, that it is difficult to discriminate between the figures of the 

 one and the other, although the plants themselves are not even allied. 



On trunks, stumps, &c. Common. May-Nov. 



Often tinged everywhere with yellow or pink. Solitary or caespitose. 

 M.J.B. Spores ellipsoid-sphaeroid, 8-10x6-7 mk. K.; 10-12x4-6 mk. B, ; 

 6x8 mk. W.G.S. Name alkali. From its alkaline odour. Fr. Monogr. 

 i. p. 214. Hym. Eur. p. 141. Icon. t. 81. /. 3. Berk. Out. p. 125. C. Hbk. 

 n. 1 86. Illust. PL 187, 225. S. Mycol. Scot. n. rfo.Schceff. t. 31, 32. 



282. A. ammoniacus Fr. Pileus fuscous blackish at the disc, 

 paler round the margin, varying cinereous, somewhat membran- 

 aceous, at first acutely conical, papillate, then campanulate, naked, 

 discoid, opaque, striate round the margin. Stem 2.5-5 cent. 

 (1-2 in.) long, 1-2 mm. (>-i lin.) thick, rooting, slightly firm, 

 polished, even, dry, equal, whitish, not becoming yellow, strigose 

 at the base. Gills simply adnate, linear, distant, distinct, whitish 

 or grey and whitish towards the apex. 



Pileus varying in colour and stature. Very much allied to A. alkalinus ; 

 odour the same, only weaker ; growth not caespitose. 



On the ground among grass. Frequent. Sept.-Nov. 



Easily distinguished from A. alkalinus by its habitat (always on the ground, 

 never on stumps) by its single (never caespitose) growth, and by its stem being 

 uniformly whitish, never becoming yellow. Spores 10-13 x 4-6 mk. B. Name 

 from its strong scent of ammonia. Fr. Monogr. i. p. 215. Hym. Eur. p. 

 142. B. 6 s Br. n. 1214. S. Mycol. Scot. n. 161. C. Illust. PI. 238. a. 



283. A. metatus Fr. Pileus 12 mm. (y z in.) or a little more 

 broad, very hygrophanous, cinereous when moist, opaque and 

 whitish when dry, somewhat membranaceous, hemispherico- 

 campanulate, obtuse, soft, when moist slightly striate, when dry 

 without strias, somewhat silky in appearance (under a lens at 

 least). Stem 5-7.5 cent. (2-3 in.) long, soft-flaccid, even, smooth, 

 whitish-cinereous, fibrillose at the base, but not truly rooted. 

 Gills simply adnate, linear, distinct, somewhat distant, whitish. 



