NON-PATHOGENIC BACILLI. 029 



in the furrows; as this extends the folds become more prominent and more 

 decidedly yellow in color, the margins are irregular, dentate, and thin; 

 along the line of inoculation very small, yellowish, punctiform colonies are 

 developed. Upon the surface of agar the growth is similar to that upon 

 gelatin. Upon potato development is very slow; first as a glistening, yel- 

 lowish-white line along the impfstrich; at the end of three weeks here and 

 there along 1 this line small, grayish-yellow, glistening masses are seen. 



261. BACILLUS KUBESCENS (Jordan). 



Found in sewage at Lawrence, Mass. 



Morphology. Bacilli with round ends, about 4 jn long and 0.9 n broad, 

 often slightly curved ; solitary, in pairs, or in short chains. 



Biological Characters. An aerobic, non- liquefy ing, motile, chromoge- 

 nic bacillus. Forms a pale-pink pigment. Spore formation not observed. 

 Movements slow. Grows best at the room temperature. Upon gelatin 

 plates the deep colonies are spherical or oval ; on coming to the surface they 

 form a projecting, porcelain- white drop; they slowly increase in size, and 

 after a time have a slight brownish color. In gelatin stick cultures a pro- 

 minent porcelain-white mass is formed upon the surface at the point of in- 

 oculation; very scanty growth along line of puncture; grows in slightly acid 

 gelatin. Upon the surface of agar a white and lustrous layer is quickly de- 

 veloped, which is at first smooth, but later becomes wrinkled ; in cultures 

 about three weeks old a slight pinkish tinge is seen. Upon potato the 

 growth is rapid and abundant; it is at first light-brown in color, and this 

 gradually changes to pink; at the end of three weeks there is a projecting 

 growth which has a delicate flesh-pink color ; the potato itself is not coloi'ed. 

 Milk is not coagulated and has an alkaline reaction ; in old cultures a slight 

 pinkish tinge is observed near the surface. Bouillon becomes slightly tur- 

 bid and a heavy white precipitate is formed. At the end of several weeks 

 a thick, tenacious film forms upon the surface. 



262. BACILLUS ALLII (Griffiths). 



Synonym. Bacterium allii. 



Found upon the surface of putrefying onions. 



Morphology. Bacilli with round ends, from 5 to 7 / long and about 

 2. 5 p broad ; solitary or in pairs ; form zooglcea. 



Biological Characters. An aerobic, chromogenic bacillus. Produces a 

 green pigment which is soluble in alcohol. Grows tolerably well on nu- 

 trient agar, and produces a bright green pellicle on the surface of this me- 

 dium. Sulphuretted hydrogen is given off by the cultures in small quan- 

 tities. 



B. Chromogenic, Liquefying Bacilli. 



263. BACILLUS FULVUS (Zimmermann). 



Found in the Chemnitz water supply. 



Morphology. Short bacilli with round ends, from 0.88 to 1.3 ju in length 

 and 0.77 // broad ; solitary, in pairs, or in chains containing several elements. 



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

 nic bacillus. Grows slowly at the room temperature best at 30 C. Spore 

 formation not observed. Forms a gamboge-yellow-colored pigment. Upon 

 gelatin plates the deep colonies are irregularly spherical, oval, or elliptical, 

 granular, and yellowish -gray in color; they are usually surrounded by pale- 

 yellow patches. The superficial colonies are reddish-yellow, drop-like, and 

 at the end of eight days measure about one millimetre in diameter. In gela- 

 tin stick cultures a prominent, arched mass of irregularly circular contour 

 and of the color of gamboge is formed about the point of puncture ; a scanty 



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