000 NON-PATHOGENIC BACILLI. 



Morphology. Bacilli with round ends, about 2. 7 n long and 0. 67 n broad; 

 occasionally form short filaments. 



Biological Characters. An aerobic, non-liquefying, non-motile bacil- 

 lus. Spore formation not observed. Grows in the usual culture media at 

 the room temperature not so well at 32 to 34 C. Upon gelatin plates (six 

 percent), at the end of twenty-four hours at 18 to 20 C., the superficial 

 colonies have a diameter of 0.5 millimetre and resemble little drops of stea- 

 rin; they have a circular and sharply defined contour, are homogeneous, 

 and of a pale yellowish-gray color ; at the end of forty-eight hours they are 

 grayish-yellow, finely granular, with irregular contour, and about one milli- 

 metre in diameter. The deep colonies are much smaller, have a greenish- 

 yellow color, granular contents, and a smooth, well-defined contour. The 

 deep colonies which come to the surface spread out to form a bluish-gray, 

 shining disc, which may attain a diameter of six millimetres. In gelatin 

 stick cultures scanty development along the line of puncture, and a grayish- 

 white, glistening layer of limited extent upon the surface. Upon the sur- 

 face of ten-per-cent gelatin a bluish-gray band with cloudy margins along 

 the impfstrich. In. bouillon cultures the liquid is diffusely clouded, but no 

 mycodermais formed upon the surface. Upon sterilized fish a shining, sticky 

 layer of a yellowish color here and there lemon-yellow; the cultures 

 have a silver-white phosphorescence in the dark, and a small quantity added 

 to a considerable quantity of sea water causes this to be phosphorescent. 

 The presence of certain salts, and especially of sodium chloride, and free 

 contact with oxygen, is favorable to the growth of this bacillus and to the 

 development of phosphorescence. 



340. BACILLUS ARGENTEO-PHOSPHORESCENS NO. III. (Katz). 



Obtained from a fragment of cuttlefish which was phosphorescent, at 

 Sydney, New South Wales. 



Morphology. Resemble Bacillus argenteo-phosphorescens No. II., but 

 the rods are a little thinner and are motile; frequently united in pairs and 

 occasionally form short filaments. 



Biological Characters. An aerobic, non-liquefying, motile bacillus. 

 Spore formation not observed. Grows at the room temperature in the usual 

 culture media not so well at 32 to 34 C. Upon gelatin plates, at the end 

 of twenty-four hours at 18 to 20 C., the superficial colonies appear as white 

 scales with irregular outlines, sometimes wrinkled, and marked with fine 

 lines or furrows, about 0.45 millimetre in diameter. The deep colonies are 

 spherical, oval, or lemon-shaped, homogeneous, and greenish-yellow in color; 

 at the end of forty-eight hours th^y appear finely granular and divided into 

 two zones. At the end of a week the superficial colonies attain a diameter 

 of about three millimetres ; they are bluish-gray and cloudy in appearance, 

 quite thin, and have a notched or dentate margin. Upon the surface of gelatin 

 stick cultures a layer is developed which extends nearly to the walls of the 

 tube, and which becomes very thin at the margins. Development occurs 

 upon the surf ace of agar, but this is not a very favorable medium. In bouil- 

 lon a diffuse cloudiness is produced and a mycoderma forms upon the surface. 

 The addition of 2.5 per cent of sodium chloride to bouillon or other media is 

 favorable to the growth and phosphorescence of this bacillus, as of those 

 previously described. Upon sterilized fish a viscid, glistening, yellowish 

 layer is developed. No growth upon acid potato. The cultures give off a 

 silver- white, phosphorescent light. Bouillon cultures commence to give off 

 light from the surface at the end of four or five days, and at the end of eight 

 days the floating mycoderma may give a light by which the time can be dis- 

 cerned,^in a dark room, from a watch ; the light is a " bluish-greenish white.'* 



