1917] BRIEFER ARTICLES 251 
be followed readily. They swelled, germinated, and produced normal 
mycelia. The hyphae were a deep blue; the growing tips were opaque 
to pale blue. Their blue color deepened with age. About 12 days after 
inoculation the medium lost its blue color, turning light yellow; the blue 
hyphae with uncolored pycnidia floated on its surface. 
METHYLENE BLUE (1/1000 of 1 per cent methylene blue’ in Pasteur’s 
solution).—The majority of conidia did not germinate, but instead 
developed vacuoles. The hyphae produced did not stain, except when 
the cells were dead. The plasmolyzed contents of the dead cells gathered 
in a blue clump in the center. These isolated dead cells distributed 
throughout the mycelium gave it a pale blue color. While the cultures 
grew more vigorously than the controls, they did not grow as well as 
the congo red and trypan blue cultures. No fruits were produced. 
NEUTRAL RED (neutral red plus 7 per cent NaCl solution diluted 
I to 500 parts Pasteur’s solution).—A few conidia germinated and grew. 
The cultures were as good as the controls. No fruits. Hyphae un- 
colored. 
Controt (Pasteur’s solution).—Conidia germinated, produced 
mycelium, but no pycnidia. 
In the case of the congo red and trypan blue cultures, it was thought 
that the mycelium had gradually stored up all the dye in the medium. 
Neutral red and salt did not stain. In those cases in which methylene 
blue penetrated the cells, it apparently was fatal. The fact that the 
solutions containing the stains supported the fungus better than the 
control medium seems to indicate one of two things: eithex. the toxicity. : 
of the dyes in the conc used (with th Pp’ neutral — 
red and salt) was enough tobe a stimul the dy h ter- 
acted the elements in Pasteur’s solution inhibitive to the growth of the 
fungus and so allowed the mycelium a better development. _ 
,* in a series of experiments with methylene blue, found 
the dye accumulated in the cell sap rather than in the protoplast of the . : 
cell. The substances which render the storage possibl 
always identical; the two which are best known a are e tannin and _phloro- 
glucin. Mycelium taken fi 
Presence of tannin and premed ay "There was no evidence of these . a. 
aed fear in the were cells. The eee —_ were ferric” : 
rous sulphate bd bong potassium bi 
