DESCRIPTION OF PLATE IV 
DEVELOPMENT IN HYMENOMYCETES 
Fig. i. —Mycelium (a), with early stages of growth ( b ) of Agaricus 
campestris (Natural size.) 
Fig. 2.—Section showing the gill-slits. (Natural size.) 
Fig. 3. —Section through a young Agaricus campestris, showing the 
veil enclosing the gills. (Natural size.) 
Fig. 4.—Adult Agaricus campestris, showing pileus (c), gills (d), 
stem ( e ), ring (/), and mycelium (g). (Three-fourths natural size.) 
Fig. 5 —Magnified section of a gill, showing the central or tramal 
layer surrounded by the subhymenial la)er, the whole invested by the 
spmre-bearing surface. 
Fig. 6.—Fragment of a gill, very highly magnified, showing trama ( t ), 
subhymenial layer (h), basidia (i), with spores (k), sterigmata (m), and 
cystidia, or barren basidia (») 
Fig. 7. —Sclerotium, with an agaric, Collybia tuberosa, growing from 
it. (Natural size ) 
