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day. During the first three days it had made a slow, poor growth, but it 

 now covered the surface with a matted growth from wliicli no hyjjhte 

 projected into the air. This medium consisted of JO c. c. agar, 20 drops 

 of saturated sohition of sodium carbonate, and 2 c. c. of Shai-p & 

 Dohme's violet litnuis solution. On the fouiteenth day there was no 

 reddening of the substratum and the surface was covered with a white 

 mycelium, but some of the hyphii- tlireads which projected out into the 

 air were bluish. At the end of 112 days the agar was nearly dry. It 

 was still blue and was covered by a bluish-white film of fungus. On 

 the glass above the agar many of the filaments of the fungus were now 

 bright blue. This stain most ])robabl3^ came from absorbed litmus 

 rather than from any pigment manufactured by the fungus. 



In horse dung sterilized with distilled water the fungus made a'white 

 growth (some yellowish hyphie). 



On banana the fungus was white on the start, but in old cultures it 

 was rose, salmon, or purple, and patches of it became bright orange 

 buff. 



In 12 days the fungus made a copious growth in the acid juice of 

 Concord grapes, and its color varied from snow white or a very feeble 

 tint (above) to purplish and rose color (below). For some days the 

 fungus was barely able to maintain itself in this very acid medium, and 

 was white, but at the end of 7 days the compact islands of mycelium 

 were roseate. After 42 days the fluid was still strongly acid, and the 

 red color persisted on litmus paper for some years. After -1 months the 

 prevailing tints were white to reddish brown. The very numerous 

 mycelial strands on the walls of the tubes above the medium Avere a 

 fine red brown (between burnt sienna and tawny). 



On Spanish onion cooked in distilled water the fungus made in 3 

 days a moderate growth, and its color varied from white to lilac (next 

 substratum); in 5 days the fungus was purplish; in 8 days there was 

 a distinct increase of purple and rose color, but there was no color in 

 the substratum under the water. After 21 days the lower part of the 

 onion iu both tubes (that part under water) retained its natural yellow 

 color, although a microscopic examination showed it to be grown full 

 of the hyphfe of the fungus. At this time the aerial mycelium was 

 white, rose, purplish, salmon, and brown (a few strands on the walls of 

 the tube). At no. time did any crimson color appear. 



In 10 c. c. of Dunham's solution with 1 per cent malic acid the fungus 

 filled the fluid and became bright rose color in 20 days, but the acqui- 

 sition of the color was slow. The litmus reaction was still decidedly 

 acid on the twentieth, thirty-fifth, and forty-fifth days. This experi- 

 ment was repeated. In 13 days the mycelium was purplish. The 

 addition of 2 per cent cane sugar to this acid Dunham favored vege- 

 tative growth, but did not increase the production of color or hasten 

 it. On the fourteenth day in one tube and on the fifteenth in the 

 other the fungus was still pure white. This experiment was repeated. 



