=Pileus= confluent with the stipe and of the same texture, gills attached, in some becoming almost free. 3 =2=--=Volva= present and distinct, annulus wanting. =Volvaria.= 140 =Volva= and annulus wanting. =Pluteus.= 138 =3=--=Stipe= fleshy to fibrous, margin of pileus at first incurved. 4 =Stipe= cartilaginous. 5 =4=--=Gills= sinuate. =Entoloma.= 143 =Gills= decurrent. =Clitopilus.= 142 =5=--=Gills= not decurrent (or if so only by a minute tooth), easily separating from the stipe. 6 =Gills= decurrent, pileus umbilicate. =Eccilia.= 148 =6=--=Pileus= slightly convex, margin at first incurved. =Leptonia.= 147 =Pileus= bell-shaped, margin at first straight and pressed close against the stipe. =Nolanea.= No species of Nolanea are described here. THE BROWN-SPORED AGARICS. (The spores are dark brown or purplish brown.) =Pileus= easily separating from the stem; gills usually free. 1 =Pileus= continuous with the stem; gills attached. 2 =1=--=Volva= wanting, annulus present. (Psalliota Fr.) =Agaricus.= 18 =Volva= present, annulus wanting. =Chitonia.= =Volva= and annulus wanting. =Pilosace.= =2=--=Veil= present. 3 =Veil= wanting or obsolete. 4 =3=--=Annulus= present, gills attached. =Stropharia.= 31 =Annulus= wanting, veil remaining attached to margin of pileus. =Hypholoma.= 26 =4=--=Stipe= tenacious, margin of pileus first incurved. 5 =Stipe= fragile, margin of pileus at first straight. =Psathyra.= =5=--=Gills= sub-triangularly decurrent. =Deconica.= =Gills= not decurrent. =Psilocybe.= But few species of Psathyra, Deconica, Chitonia and Pilosace are noted from the United States. None are here described. THE BLACK-SPORED AGARICS. =Pileus= present to which the gills are attached. 1 =Pileus= wanting, gills attached to a disk at apex of stem from which they radiate. =Montagnites.=[G] =1=--=Gills= more or less deliquescing, or pileus thin, membranous and splitting between the laminæ of the gills and becoming more or less plicate. =Coprinus.= 32 =Gills= not deliquescing, etc. 2