GREEN FLUORESCENT BACTERIA FROM WATER 87 



or derivatives of such; (d) introduced pigments; (e) reserve pig- 

 ments or pigments associated with reserves. 



Sullivan also reports Beyerinck's (1891) division of chromo- 

 genic bacteria, which is as follows: (a) Chromophorous bacteria 

 — forms in which the pigment serves some pm-pose in the cell, 

 as chlorophyll; (b) chromoparous bacteria — forms which excrete 

 the pigment as a waste substance; and (c) parachrome bacteria 

 — forms which retain the pigment in their cells. 



The subject of bacterial pigments has been much discussed; 

 but only a few of the publications will be mentioned here. Was- 

 serzug (1887) studied B. pyocyaneus or the organism of green 

 pus and found that in the same cultures not all the cells pro- 

 duced the same pigment. To avoid this variation as far as 

 possible, he worked with cultures which had been rejuvenated 

 by successive transfers and inoculations into rabbits. Wasser- 

 zug states 



II semble qu'on puisse distinguer deux periodes dans la vie de I'or- 

 ganisme colore: dans la premiere i] prefers et accommoda a ses besoins 

 son milieu de culture; dans la second, il produit et secrete, la matiere 

 colorante. 



He tried the effects of antiseptics and found that the points 

 where pigment formation and growth stopped differed but 

 slightly. This would seem to indicate that the colored pigment 

 was merely a waste produce resulting from cellular metabolism. 



Jordan (1899) studied the conditions under which the dif- 

 fusible fluorescent pigment was produced. He used synthetic 

 media and concluded that the presence of phosphorus and 

 sulfm* was essential to vigorous fluorescing properties. He 

 added that the fluorescent property might be of no benefit to 

 the cell. 



Babes (1889) studied the colored materials from B. pyocyaneus. 

 To secure his pigments he inoculated neutral peptone gelatin 

 with a strain isolated from an abscess. The medium was inocu- 

 lated and left for six weeks at room temperature. The color 

 varied and an odor of linden flowers was noticeable. Babes 

 uged solvents and distillation methods to remove his pigment, 



