1920] WILLAMAN—SCLEROTINIA 225 



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soluble in ammonium oxalate, with the concomitant formation of 

 crystals of calcium oxalate. In accordance with the usual nomen- 

 clature (2, 5, 10), therefore, the coagulum is judged to be calcium 

 pectate, and its formation to be brought about by the enzyme 

 pectase, secreted by the fungus. Cooley demonstrated a similar 

 pectic enzyme, differing from the present one, however, in that it 

 brought about the coagulation in the supposed absence of calcium. 

 He designated his enzyme pectinase, but that is merely a question 

 of nomenclature. As regards the necessity for the presence of 

 calcium, it is possible that the pectin preparation used by Cooley 

 contained some of this element, brought down during the alcoholic 

 precipitation. He states that a preliminary test of the plum juice 

 with oxalic acid showed the absence of calcium, and that this 

 treatment was therefore abandoned as unnecessary. It is incon- 

 ceivable that a fruit juice should contain no calcium whatever; 

 hence it is very probable that the pectin coagulated by alcohol 

 did contain some calcium, since the latter is a characteristic con- 

 stituent of the alcholic precipitate of all plant juices. 



In order to determine to what extent pentosans are present in 

 the mycelium of Sclerotinia. either as enmeshed pectic gel or as 

 an actual constituent of the fungous body, a few analyses were 

 made of felts grown on various media. The felts were removed 

 from the media, carefully washed with water, dried between filter 

 paper, and then placed in a desiccator over quicklime. When per- 

 fectly dry they were ground to a powder, sampled, and analyzed. 

 The following data were obtained, expressed as percentage of 

 pentosan in the dry mycelium: 



No. 568. Grown on synthetic sucrose-salts media en- 

 tirely free from pectin and pentose; sporula- 

 tion abundant 3 • 5 P er cent pentosan 



No. 569. Grown on whole prune juice, pectin fairly 



abundant ; sporulation moderate 1.5 per cent pentosan 



No. 570. Grown on whole peach juice and apricot juice, 



pectin abundant; sporulation abundant 0.8 per cent pentosan 



Xo. 572. Grown on the prepared pectin medium de- 

 scribed ; sporulation absent 3.9 per cent pentosan 



That the figure obtained in no. 568 actually represents the 

 pentosan content of the mycelia is doubtful. When the phloro- 

 glucin was added to the furfural-containing distillate, a bright red 



