=luteoalba=, Bolton. P. 1-2 cm. campan. then exp. and umb. pale yellow; g. adnate, broad, white; s. 3-5 cm. shining, glabrous, yellowish; sp.

=flavoalba=, Fr. P. 1-5 cm. exp. umb. often cracked at margin, yellowish or white; g. soon free, distant; s. 2-3 cm. white, pellucid, apex pruinose; sp. 6-8 3-4.

_M. lactea_ differs in adnate gills and downy base of stem.

_M. luteoalba_ has a yellowish stem.

=lactea=, Pers. White. P. 1-1.5 cm. sub.u.mb. striate, even when dry; g.

adnate, narrow, crowded; s. 3-5 cm. toughish, not quite straight, glabrous; sp. 7-8 3-4.

Differs from _M. gypsea_ and _M. tenuis_ in scattered habit.

var. _pithya_, Fr. Smaller, p. becoming almost plane; s. thin, base bubillose, downy.

forma _pulch.e.l.la_, Fr. Milk-white; g. linear, ascending; s. attenuated.

Solitary.

[=olida=, Bres. Smell very strong, rancid. P. thin, conico-campan.

obtuse, then exp. and umb. yellow soon pale straw; g. uncinato-decur.

connected by veins, white; s. hyaline, strigosely rooting; sp. 8-9 6.

=gypsea=, Fr. Caespitose. Pure white, rarely with a yellow tinge. P. 1-2 cm. conical then campan. striate up to umbo, glabrous; g. subuncinate; s. 5-7 cm. straight, narrowed upwards from hairy base; sp. 8-9 4.

[=nivea=, Q. Shining white. P. sulcate, diaphanous; g. uncinate; s.

pruinose, base rather swollen, fibrillose.

[=galeropsis=, Fr. P. conico-camp. even, gilvous; g. free, whitish; s.

straight, narrowed upwards, fragile, not rooting, ferruginous below.

[=nucida=, Brig. P. campan. obtuse, even, downy under a lens, deep rust-colour, hygr.; g. free, white then rosy; s. silky shining, base snow-white, apex mealy.

[=Benzonii=, Fr. P. very thin, campan. exp. umbil. finely striate, pallid or reddish; g. white; s. equal, glabrous, white.

An introduced species.

[=melanops=, West. P. convexo-camp. plicate, umbo blackish-brown; g.

adnexed to a collar; s. slender, glabrous base fibrillose.

[=pruinatus=, Fr. Shining white. P. thin, conico-campan. papillate, edge deflexed, sulcate, pruinose; g. crowded; s. bulbous, naked.

III. RIGIDIPEDES. _Stem firm, rigid, rather tough, juiceless, base strigosely rooting, gills discoloured, grey, reddish, &c., often connected by veins._

=cohaerens=, Fr. P. 2-3 cm. camp. obtuse, tawny cinnamon, soft and velvety; g. free, distant, very broad, pallid; s. 8-12 cm. h.o.r.n.y, rigid, even, shining, bay, base downy, rooting; sp. 10 7-8.

[=raeborhiza=, Lasch. P. acute camp. exp. glabrous, striate, rather tawny then pale; g. almost free, connected by veins; s. even, floccosely pruinose, rooting, tinged tawny.

=prolifera=, Sow. Caespitose. P. 1-2 cm. camp. then exp. sub.u.mb., margin coa.r.s.ely striate, yellowish tan; g. adnexed; s. 6-8 cm. glabrous, shining, striate, brownish below, rooting; sp. ----.

=excisa=, Lasch. (non Berk.). P. 2-3 cm. camp. then obtuse, greyish fuscous or pallid; g. scarcely adnexed, narrowed behind, very broad in front, pallid; s. 2-3 cm. tough, even, grey, rooting; sp. ----.

Differs from _M. polygramma_ in smooth stem.

var. _f.a.getorum_, Fr. Slender. P. even, striate to middle, smoky or livid then pale; g. joined to a collar; s. incurved at base, fixed to leaves by down.

=rugosa=, Fr. P. 2-5 cm. camp. then exp. sub.u.mb. tough, irreg. radially rugulose, greyish; g. arcuately adnate, white then tinged grey; s. 3-4 cm. tough, even, glabrous, pallid; sp. ----.

=sudora=, Fr. White. P. 2-3 cm. umb. striate, viscid; g. obtusely adnate, sometimes tinged pink; st. 6-10 cm. even, dry, rooting; sp.

=galericulata=, Scop. P. 2-5 cm. conic camp. exp. striate up to umbo, dry, brownish, livid, &c.; adnate with decurrent tooth, connected by veins, pinkish when old; s. 5-8 cm. polished, even, glabrous; sp. 6-7 4.

_M. rugosa_ differs from present sp. in having grey gills and rugulose pileus.

[=simillima=, Karsten. P. conico-campan. even, dry, glabrous, livid or dingy pallid; g. emarginato-decur. crowded, white, very slightly tinged rose; s. fragile, polished, even, glabrous, base curved, rooting; sp.

Very near to _Mycena galericulata_, differing in being fragile and in becoming pale.

=polygramma=, Bull. P. 3-7 cm. conic camp. sub.u.mb. dry, striate, dark grey or blackish-blue when young; g. pale pinkish-grey tinge; s. 7-12 cm. rigid, tough, shining, longitudinally striate, strigosely rooting, grey; sp. 11-12 6.

Differs from _M. plicata_ in striate stem.

[=inclinata=, Fr. P. camp. obtuse, striate to middle, everywhere brownish; g. adnate, whitish, base grey; s. rigid, twisted, pruinosely fibrillose, upwards interruptedly striate.

=parabolica=, Fr. P. 2-5 cm. oval then camp. striate to middle, disc blackish-violet, margin paler, becoming pale; g. adnate; s. 4-7 cm.

even, glabrous, base strigose, dark coloured; sp. 11-12 6.

Differs from _M. galericulata_ in absence of decurrent tooth of gills, also their pinkish colour.

=tintinabulum=, Fr. P. 2-3 cm. tough, camp. even, bay, yellow brown, pallid, &c., viscid when moist; g. adnate with a decurrent tooth, crowded; s. 2-3 cm. even, glabrous, pallid, strigosely rooting; sp. 7-8 5.

Differs from _M. galericulata_ in short stem and even pileus.

=Berkeleyi=, Ma.s.s. (= _excisa_, B.). P. 3-7 cm. camp. striate up to umbo, hygr. dingy brown then paler; g. broadly sinuate with decurrent tooth, tinged flesh colour; s. 7-12 cm. long, purplish brown, base rooting; sp. 5 3.5.

[=laevigata=, Lasch. Constantly white. P. hemispher.-exp. obtuse, even when dry; g. with decur. tooth, crowded, distinct, joined to a collar; s. even, glabrous, lubricous, base strigose.

Requires to be carefully distinguished from white forms of _M.

galericulata_ and _M. rugosa_. S. lubricous when moist, not viscid.

[=lasiosperma=, Bres. Caespitose. P. thin, conico-campan. exp. umb. edge then upturned, rather viscid, striate to umbo, livid grey with a grey bloom at first; g. sinuato-unc. connected by veins, whitish then grey; s. pallid above, chestnut and white-pruinose below; sp. globose, aculeate, 6-7.

IV. FRAGILIPEDES. _Stem fragile, dry, juiceless. Pileus hygrophanous. Gills often discoloured._

=atroalba=, Bolton. P. 2-3 cm. campan. obtuse, disc blackish or fuscous, whitish towards striate margin; g. free, crowded, glaucous; s. 6-10 cm.

pallid, apex darker, base swollen, strigose; sp. ----.