DESCRIPTION OF PLATES 
Plats XXI. Fig. i.— Polyporus dryophilus: A median-longitudinal section of a 
sporophore on Quercus alba from Arkansas, showing the granular 
core and the white mycelial lines in the central and rear portion. 
Fig. 2.— Polyporus dryophilus: Side view of the ungulate type of sporo¬ 
phore on Quercus californica from California. 
Fig. 3.— Polyporus dryophilus: Median-longitudinal section of the glo¬ 
bose type of sporophore on Quercus garryana from California, showing 
the large granular core and prominent white mycelial lines. 
Fig. 4.— Polyporus dryadeus: Median-longitudinal view of a young 
sporophore on Quercus texana from Texas, showing the fibrous, non- 
granular nature of the context. 
Fig. 5.— Polyporus fulvus Fries: Median-longitudinal view of a sporo¬ 
phore on Quercus sp. from Sweden, showing the granular core char¬ 
acteristic of P. dryophilus . 
Fig. 6.— Polyporus vulpinus: Median-longitudinal view of sporophore 
on Populus sp. from Sweden, showing the granular core character¬ 
istic of P. dryophilus. 
Fig. 7.— Polyporus dryophilus: Front view of the applanate type of a 
sporophore on Populus tremuloides from Colorado, showing the faint 
zones on the pileus where the hairs have disappeared. 
Fig. 8.— Polyporus dryophilus: Median-longitudinal view of sporo¬ 
phore on Populus tremuloides from Colorado, showing the granular 
core originating between the sapwood and bark and extending into 
the center of the sporophore. 
XXII, Fig. 1.— Polyporus dryophilus: Radial-longitudinal view of the rot 
occurring in Quercus sp. from Europe and said to be the rot pro¬ 
duced by P. dryadeus. 
Fig. 2.— Polyporus dryadeus: Cross section of a small root of Quercus 
alba from Maryland, showing the mottled appearance of the diseased 
wood in the middle stages of the rot. 
Fig. 3.— Polyporus dryophilus: Radial-longitudinal view of the rot ap¬ 
pearing in Quercus alba from Arkansas, showing the advancing line 
of rot in a branch. 
Fig. 4.— Polyporus dryadeus: Upper surface of a sporophore on roots of 
Quercus texana from Texas, showing the rough tuberculate pileus. 
Fig. 5.— Polyporus dryadeus: Rot occurring in an apparently sound 
root of Quercus alba from Virginia, showing cross section of a dis¬ 
eased root, immediately adjacent to the point of attachment of a 
large sporophore of P. dryadeus , 1 foot high and 1 foot wide. Some 
sound, living wood is still present. 
Fig. 6.— Polyporus dryadeus: Cross section of diseased root of Quercus 
alba from Virginia, showing the nearly sound, living upper half of 
the root and the badly diseased lower half. 
(25°) 
