Micro-organisms of Maple Sap 517 



Capsule. — There was a tendency to develop a slimy sediment 

 in liquid cultures, but microscopic examination and staining 

 methods failed to demonstrate a capsule. 



Zooglea. — Xo evidence of zooglea masses was observed. 



Involution forms. — Involution forms were not observed. 



Staining reactions. — The organisms stained readily in 1-10 

 cold watery fuchsin, gentian violet, Loeffler's alkaline methylene 

 blue, and carbol fuchsin. The method of Gram gave negative or 

 sometimes doubtful results. 



Cultural Characters 



Agar stroke. — Growth was moderate becoming visible two 

 days after inoculation. It was raised, regular, slimy, and tinged 

 with pink. Iridescence developed after 10 days, the growth hav- 

 ing spread to a width of 4 to 5 mm. 



Agar stab. — Slight growth became visible after 24 hours. The 

 second day a characteristic surface colony appeared. The growth 

 in old cultures (6 to 8 weeks) became villous along the line of 

 puncture. Colonies were first gray, and then became pink. When 

 7 days old they were from 2 to 4 mm. in diameter, raised, shiny, 

 and pigmented. The edge was regular, thin and transparent, and 

 the center opaque. 



Two percent sucrose litmus agar. — Growth was confined to 

 the surface, and characterized by the production of pink pigment. 

 Acid was produced but the litmus was not reduced. 



Two percent dextrose litmus agar. — Acid production became 

 apparent the second day. Reduction of the litmus began after 

 one week and progressed slowly until complete about the fourth 

 week. 



Two percent lactose litmus agar. — Growth was slight, acid 

 formation and litmus reduction 1x)th being absent. 



Five percent glycerin litmus agar. — The growth was slow 

 and acid production absent. Feeble litmus reduction was noted 

 on the fifth day. and thereafter progressed slowly, becoming com- 

 plete after two weeks. 



