128 HEART-ROT CAUSED BY OTHER FUNGI 
already eaten and destroyed by insect larvae. It is never 
perennial. 
The inner part of the fructification is mainly composed 
of masses of parallel, very tender, richly septate, red brown 
hyphae, filled with protoplasm. On the upper side many 
of the masses run up into the scales that project from the 
upper surface ; those on the lower side run down into the 
trama between the pores, and ac- 
cording to Hartig it is the escape 
of the contents from these hyphae 
that gives the red colour on bruis- 
ing. The pores are irregular in 
shape (fig. 47), and from 0:5 to 
2 mm. in diameter. Their depth 
is about 5 mm. Near the stipe 
the pores are long and labyrin- 
thine, but the margin is barren 
until marginal growth has ceased, 
when pores are formed out to the 
edge. Inside, the pores are lined 
by the hymenium, which is com- 
posed of basidia and various forms 
ie. 48-—Riyrnanial layer of paraphyses. The basidia are 
of Polyporus Schweinitzii, colourless or very pale yellow, 
oe ie 30-40 X 5-8. The spores are 
a Svan ei (300). > about 4% 6 » (fig. 48). In addition 
to the basidia there are numerous 
thin-walled paraphyses and larger specialized thick-walled 
paraphyses (cystidia). As shown in this figure the cystidia 
are very variable in shape and size. They have deep brown 
contents, and the large brown hyphae which carry them can 
often be traced for some distance back into the trama. The 
cystidia project into the pores beyond the basidia, and 
often bear drops of liquid at their extremities to which 
spores adhere. Thus it appears that the cystidia obstruct 
the normal dispersal of the spores. 
When the fructifications are growing actively the spores 
fall from them in clouds, dense enough to be seen with the 
