Pileus first slightly silky, soon becoming smooth, very dry, neither moist, viscid, water-soaked, nor distinctly scaly; rather thin, opaque, absorbing moisture, but is the same color as the gills. Stem fibrous, by which the smaller species resembling Collybia may be distinguished. * Gills broad, rather thick, somewhat distant. **:sericella2 Gills narrow, thin, crowded. B. PILEUS EVEN, SMOOTH, NOT DOWNY NOR SCALY, NOT VISCID. In rainy weather moist; when very young pruinose (but rarely conspicuously) from the universal veil. Flesh soft and spongy or very thin when it is water-soaked. GUTTATA (_gutta_, a drop). Page 76. Pileus fleshy, soft, fragile, marked with drop-like spots or rivulose. Appearing in spring, rarely in autumn. Cespitose, in troops or often in rings. * Gills whitish. ** Gills becoming reddish or smoky-gray. [Illustration: Grouped by F.D. Briscoe—Studies by C. McIlvaine. PLATE XVIII.] FIG. PAGE. FIG. PAGE. 1–2. TRICHOLOMA PERSONATUM, 79 5. TRICHOLOMA 68 COLUMBETTA, 3. TRICHOLOMA RUSSULA, 65 6. TRICHOLOMA HUMILE, 81 4. TRICHOLOMA TERREUM, 71 SPONGIOSA (_spongia_, a sponge). Page 78. Pileus compact, then spongy, obtuse, even, smooth, moist but not hygrophanous; firm, growing in troops late in the autumn. Stem stout, base usually thickened, spongy fibrous. Gills at length decurrent but sinuate, by which character they are distinguished from Clitocybe. * Gills not discolored. ** Gills discolored. HYGROPHANA (_Gr._, wet; to appear). Page 80. Pileus thin, somewhat umbonate; flesh at length soft, watery. Stem rootless, containing a pith, entirely fibrous. Flesh not exceeding in depth the width of the not broad, thin gills; thinnest toward the margin, hence somewhat umbonate. Color of the pileus either moist or dry, very variable in the same species. Pileus sometimes pulverulent from the persistence of the veil in dry weather. * Gills whitish, not spotted. ** Gills more or less violet, gray or smoky. Not represented. _Series A._ PILEUS VISCID OR FIBRILLOSE, DOWNY OR SCALY. I.—LIMA´CINA. Viscous when moist. * _Gills not becoming discolored, nor becoming reddish._ =T. eques´tre= Linn.—_equestre_, belonging to a horseman or knight, from distinguished appearance. =Pileus= fleshy, compact, convex becoming expanded, obtuse, pale-yellowish, more or less reddish tinged, the disk and central scales often darker, the margin naked, often wavy. =Flesh= white or tinged with yellow. =Gills= rounded behind, close, nearly free, _sulphur-yellow_. =Stem= stout, solid, pale-yellow or white, white within. =Spores= 6.5–8×4–5µ. =Pileus= 3–5 in. broad. =Stem= 1–2 in. long, 6–10 lines thick.