=T. subpulverulen´tum= Pers.—slightly dusty. =Pileus= 1–2½ in. across, convex then plane or depressed in center, even, innately pruinose, hoary, white, whitish, grayish, margin extending as a slight rim incurved beyond gills. =Flesh= white, thick, firm, hygrophanous. =Gills= rounded without a tooth, close, narrow, white. =Stem= 2–3 in. long, 3–5 lines thick, equal, solid, somewhat striate, whitish. =Spores= 5×3µ _Massee_; 4×3µ _W.G.S._ Biological grounds, University of Pennsylvania. Philadelphia. May to November, 1898. _McIlvaine._ A species one is glad to find. It has a healthy substantial presence full of promise. It is a solitary grower among grass on lawns and pastures, but its individuals are neighborly. Caps and stems are excellent. [Illustration] Grouped by F.D. Briscoe—Studies by C. McIlvaine. PLATE XXIV. FIG. PAGE. FIG. PAGE. 1–2–3. CLITOCYBE 108 8. CLITOCYBE AMETHYSTINA, 107 OCHROPURPUREA, 4. CLITOCYBE 108 9. CLITOCYBE ODORA, 90 OCHROPURPUREA (SECTION), 5. CLITOCYBE MAXIMA, 99 10. CLITOCYBE LACCATA, 107 6. CLITOCYBE MAXIMA 99 11. CLITOCYBE 100 (SECTION), INFUNDIBULIFORMIS, 7. CLITOCYBE NEBULARIS, 85 CLITO´CYBE Fr. _Gr._—sloping. (From the depression of the pileus.) =Pileus= generally fleshy, becoming thin toward the margin, flexible or tough, plane or depressed, margin involute. =Gills= adnate or decurrent, never sinuate. =Stem= confluent and homogeneous with flesh of pileus, somewhat elastic, with a spongy stuffing, frequently becoming hollow, externally fibrous. Universal veil when present conspicuous on the pileus like frost or silky dew, but commonly wanting. Growing on the ground, frequently in groups. The thinner and hygrophanous species appear late in autumn. Some are quite fragrant. Collybia, Mycena and Omphalia are separated by their stems being cartilaginous, not externally fibrous as in Clitocybe. Tricholoma by its sinuate gills. Variations in species of Clitocybe are great. A few are easily fixed in the genus, but many of them will puzzle the amateur and perplex the expert. The gills are always attached to the stem, and usually run down it. They are not notched next to the stem as in Tricholoma. Like Tricholoma, Clitocybe has many species, most of which are common, and are probably edible. I therefore give Professor Peck’s description of all Clitocybes thus far submitted to him. I know of but one species which is injurious to some persons—Clitocybe illudens. Many eat and enjoy it. It does not agree with others. A few untried species are suspicious to a like extent. Clitocybe illudens possesses the property of phosphorescence.