fHARRisox et barlow] SLIME-PRODUCING ORGANISM 99 



The gelatin without carbohydrates developed only a yellow-green 

 tint, and no pigment grains. Colorless crystals were very numerous in 

 the gelatin. In form they were twin pyramids with square bases placed 

 base to base and the plane of the base horizontal. Isolated colonies 

 were each surrounded at a certain distance in the gelatin by a ring or 

 zone of such crystals, but between crowded colonies the crystals were 

 thickl}- strewn. In the gelatin with sugar there were no crystals or at 

 least none in those parts of the plate where sugar was present as indicated 

 by the rich pigmentation. With starch and with dextrin there were 

 crystals, especially where there was least pigment. Crystals never formed 

 in a zone around a colony containing pigment grains. 



In twelve days all the plates of this series were liquefied and the 

 blue and violet pigment was discharged, leaving the liquefied gelatin 

 yellowish or greenish yellow and very slimy. Some violet and blue 

 pigment remained, however, in the sucrose gelatin. 



Stab Cultures in Gelatin with Carbohydrates. — Stich cultures in 

 gelatin of the same composition as that used for the plate cultures be- 

 haved as follows: — 



