The North American species of Psathyrella.

19721

PSATHYRELLA

411

388. Psathyrella agrariella (Atkinson) A. H. Smith, comb. nov.
Psilocybe agrariella Atkinson, Ann. Mycol. 7: 374. 1909.
var. agrariella
Pileus 1-3.5 cm broad, convex to expanded, the margin incurved slightly, at
times obtuse at first and becoming obtusely campanulate, surface glabrous or with
a few fibrils from the rudimentary veil along the margin, hygrophanous, pale
reddish brown to pale rufous at first, tinged umber at maturity, fading to pallid
ochraceous or pinkish buff, pellucid striate when moist, at times slightly rugose.
Context thin and fragile, odor and taste not distinctive.
Lamellae adnate, seceding, close, moderately broad and often ventricose, at
length dull purple-brown, edge white fimbriate.
Stipe 4-6 cm long, 1.5-3(-4) mm thick, equal, fragile, even, apex pruinose,
glabrous or with scattered fibrils from the veil when very young, soon hollow,
white above, becoming sordid brownish toward the base, base white mycelioid.
Spores 7-9 (-10.5) x 4-5 (-5.5) a, smooth, apical pore present but small and not
affecting the shape of the apex, shape in face view ovate to elliptic, in profile
obscurely inequilateral, color in KOH dull cocoa-color slowly darkening to
chocolate-brown, in Melzer's tawny, wall about 0.3 pu thick.
Basidia 4-spored, 17-20 x7-10 /, short-clavate, hyaline in KOH. Pleurocystidia abundant, fusoid-ventricose, 48-60 x 10-14 /t, tapered evenly to an obtuse
to subacute apex (3-4 A broad), wall thin, smooth and hyaline, cell content not
distinctive in KOH or Melzer's. Cheilocystidia abundant, broadly ventricose,
mucronate (but with homogeneous hyaline content) or saccate, 22-30x 10-16 /,
slightly yellowish revived in KOH in some.
Gill trama regular, the hyphae somewhat interwoven, when revived in KOH
pale cinnamon-brown. Pileus having a cuticle of vesiculose to pear-shaped cells
but these not arranged in a definite palisade. Context of interwoven hyphae and
pale cinnamon-brown when revived in KOH.
Type locality. Ithaca, New York.
Habit and habitat. Gregarious on moist soil in woods and shady places.
Distribution. Michigan, New York, Tennessee, Utah.
Observations. This is a much more common species than the records indicate.
Material examined. Michigan: Kauffman 8-19-21; Potter 9071; Smith 25099,
25140, 25252, 28674, 28700, 28713, 32063. New York: Kauffman 9-7-14.
Tennessee: Hesler 11195. Utah: McKnight F949.
388a. Psathyrella agrariella var. ochrofulva A. H. Smith, var. nov.
Pileus 8-15 (-20) mm latus, late convexus, ad marginem tenuiter fibrillosus vel
floccosus, glabrescens; pallide fulvus; contextu ochraceo-fulvus; lamellae pallidae
demum brunneolae dein fusco-brunneae, demum subdistantes; stipes 2-3 cm longus, 1.5-2.5 mm crassus, albus demum pallidus, deorsum demum melleus vel
isabellinus; velum pallide fibrillosum; sporae 7-9(-10) x3.8-4.5(-5) /u; pleurocystidia 40-60x 9-14 u, fusoide-ventricosa, subacuta vel interdum cum 1-3 processis; fibulae adsunt. Typus. Smith 33628 (MICH); legit prope Burt Lake,
Michigan.
Illust. P1. 88, fig. a.
Pileus 8-15 (-20) mm broad, obtuse to convex when young expanding to
broadly convex or plane, margin somewhat incurved at first, surface moist and