94 



Mycologia 



did make a statement," he says, " to this effect : '■ The term agency 

 rather than organism is employed because it is hoped to avoid any 

 possible prejudice to the direction in which such research may lead. 

 It is distinctly felt that any assumption tacitly ascribing such dis- 

 eases, because infectious, to organisms of the known or usual types 

 may serve in the end to restrict rather than broaden the investiga- 

 tion/ Moreover, because I was able to determine more or less 

 definitely the dimensions of the infectious agency I did not state 

 as quoted that ' therefore,' it ' can not be a germ or similar organ- 

 ism/ Finally, I do not term it a ' living fluid contagion,' but did 

 merely quote from Beijerinck his well-known expression, 'con- 

 tagium vivum fluidum/ " Fortunately, Dr. Duggar's paper will 

 shortly be- published in full and those interested in the subject will 

 at once forget my inaccurate report of it. 



Enzyme action in P. volvatus and F. igniarius is discussed by 

 Schmitz in the Journal of General Physiology for July, 192 1. 

 From the standpoint of parasitism, Polyporus volvatus is one of 

 the most interesting of the wood-destroying fungi. Although no 

 inoculation experiments have been made, numerous observations 

 tend to confirm the opinion of the writer that it is truly parasitic. 

 Throughout Washington, Oregon, and Idaho it is not at all un- 

 usual to find fruiting bodies appearing in great numbers over prac- 

 tically the entire surface of the trunk of Douglas fir, white fir, and 

 western hemlock. This condition may be observed on trees still 

 having a green, healthy foliage as well as on trees which to all 

 appearances have been killed by the fungus. 



Cultures of Polyporus volvatus and Fomes igniarius were ob- 

 tained from the young sporophores by the tissue method. In 

 D. volvatus the presence of the following enzymes was demon- 

 strated: esterase, maltase, lactase, sucrase, raffinase, diastase, inu- 

 lase, cellulase, hemicellulase, glucosidase, rennet, and catalase. In 

 F. igniarius the presence of the following enzymes was demon- 

 strated : esterase, maltase, lactase, sucrase, raffinase, diastase, inu- 

 lase, cellulase, hemicellulase, glucosidase, urease, rennet, and cata- 

 lase. 



