A Bacterial Disease of Stone Fruits 401 



Gelatin streaks. — On slanted gelatin (+15) at room temperature of 

 about 25° C, the streak having been made with a one-millimeter loop, 

 a light, semi-transparent growth was noticed after two days along the 

 entire path of the loop. In four days there was a slight liquefaction 

 along the streak. On the fifth day the growth was amber yellow (1) in 

 color, liquefaction had extended the entire length of the streak, and the 

 growth was about ten millimeters wide and five deep. On the eighth day 

 all material in the slant down to three millimeters below the base of the 

 slant had been liquefied. Complete liquefaction occurred in from twelve 

 to thirty clays. 



Gelatin stah. — In gelatin stab the path of the needle became beaded, 

 but usually in the upper twenty-five millimeters of the medium it at first 

 became more or less filiform. The growth on the surface was most rapid, 

 and liquefaction, which began about the third clay, soon passed to the walls 

 of the tubes and then slowly downward. The growth in the depth of the 

 gelatin soon ceased and the material along the track of the needle was not 

 liquefied more rapidly than that away from its path. The liquefied 

 gelatin was at first more or less clouded and was of about the same color 

 as the solid material, but later it cleared and took on a raw sienna (2) 

 color, A bacterial layer Naples yellow (3) in color soon formed on the 

 solid gelatin and gradually settled as the material liquefied. Both a 

 rim and a pellicle, cream yellow (2.) in color, finally formed. Complete 

 liquefaction occurred in from several days to six weeks or longer, depending 

 on the temperature, the strain of the organism, and the composition of 

 the culture material. In four months the liquefied material was viscid, 

 was raw sienna (4) in color, and had a thick, slimy, Naples yellow (3), 

 bacterial deposit in the bottom of the tube. 



Hiss-glucose colonies. — Plantings made on Hiss-glucose from six-days- 

 old bouillon cultures came up in from two to ten days (usually from four 

 to seven) at room temperature of from 23° to 25° C, forming colonies from 

 one to four millimeters in diameter in about eight days. No growth 

 occurred at 37° C, but at 25° C. colonies appeared in forty-eight hours. 

 The colonies were at first almost white, translucent, moist, and glisten- 

 ing, but later became amber yellow (1). When not crowded, the surface 

 colonies were round, with an entire edge, the surface being smooth with 

 a more or less convex elevation, and the internal structure being finely 

 granular. The deeper colonies were elliptical or'lenticular in form. Plates 



