Micro-organisms of Maple Sap 523 



XLIX failed to grow in tubes exposed at 44 C. or alx>ve, Cl\ al 

 46 C, and CXXIV and CVI at 48 C. 



Desiccation, — Sterile cover glasses were plaeed in Petri dishes 

 and inoculated, each with a loop of media from a 12 day old broth 

 culture, and allowed to dry for intervals varying from the first 

 instant when the cover glasses were free from the film of moisture 

 up to 30 days. Their viability was tested by transferring the 

 cover slips to tubes of broth by means of sterile forceps. The 

 cultures were held for two months but in every instance failed to 

 show growth. 



Insolation. — Thinly sown agar plates were exposed on snow 

 to direct sunlight for 30 minutes with one-half covered. After a 

 period of incubation the colonies which developed on the exposed 

 and unexposed portions of the plates were counted. There was 

 practically no difference in the number of colonies developing. 



Pigment formation. — Pigment formation occurred only in 

 the presence of oxygen and at ordinary temperatures. It failed 

 entirely at 37° C. Upon solid media such as agar and gelatin each 

 coccus had its peculiar tinge of pink. An attempt was made to 

 refer these colors to the chart given by Winslow, 1 as follows: 



The pigment was insoluble in water, dilute sulphuric acid, xylol, 

 cold or hot alcohol, and chloroform. In dilute nitric acid the 

 growth was disintegrated and the pigment dissolved slightly. 



C. THE GREEN FLUORESCENT BACTERIA 

 OCCURRING IN MAPLE SAP 



Introduction 



Bacteriological literature contains descriptions of more than 

 50 species of bacteria which are capable of producing a green 

 fluorescent pigment. Such bacteria were originally assigned to 



1 Winslow. Systematic Relationships of the Coccaeea? (1908). 



