Fitzpatrick: A Parasitic Species of Claudopus 35 
condition, and the sporophores of the Polyporus produce their 
hymenium and spores in the normal manner. Thin sections made 
through the point of attachment of the stipe of the parasite to the 
host disclose no marked derangement of the elements of the latter. 
It is possible to trace to some extent the course of the hyaline 
hyphae of the Claudopus among the deeper-colored threads 
making up the sporophore of the Polyporus. Some of these are 
found ramifying the trama of the host to a considerable depth. 
It is possible that they extend through its stipe to the soil. The 
presence of fruit bodies of the parasite on the stipe furnishes some 
indication of this. 
The mycelium of the parasite is relatively small in amount, and 
the hyphae of the two fungi lie in close contact and run approxi- 
mately parallel. Careful search fails to reveal any organs of the 
nature of haustoria, and dissolution of the host hyphae by en- 
zymes excreted by the parasite appears not to take place. If any 
such process occurs, the disintegration of the host is insufficient 
in amount to be evident in thin, free-hand sections. 
The method by which natural infection occurs was not deter- 
mined. Fruit bodies of the Claudopus leading a saprophytic ex- 
istence on neighboring twigs or soil could not be found. It is not 
impossible, however, that these were produced earlier and had 
already disappeared. Local infection of the sporophores of the 
Polyporus might result either from spores produced on such 
saprophytic fruit bodies or from hibernated spores produced the 
preceding year on parasitic fruit bodies. It seems more probable, 
however, that the vegetative mycelium of the Claudopus spreads 
in the soil and travels upward among the hyphae of the Polyporus 
during the development of its sporophore. It may thus retain 
organic connection with the food material in the soil and be par- 
tially or wholly independent of the Polyporus in its food relation- 
ships. 
The upper figure in the accompanying plate illustrates well the 
fruit bodies of the two fungi. A compound structure resulting 
from the fusion of the pilei of three sporophores of the host plant 
is shown. The blur at the center of the photograph results from 
the failure of the stipe of the sporophore to fall into focus. The 
tendency of the sporophores of Polyporus perennis to fuse at the 
