NON-PATHOGENIC BACILLI. 675 



faction occurs in funnelform along the upper portion of the line of inocu- 

 lation and gradually extends downward; an abundant deposit is seen at the 

 bottom of the tube, and the liquefied gelatin above is but slightly clouded ; 

 no mycoderma forms upon the surface. Upon the surface of agar a whitish 

 layer is developed which is easily separated from the culture medium. Upon 

 potato a thick, cheesy, yellowish-white layer is quickly developed along the 

 line of inoculation ; in potato cultures an abundant development of spores 

 occurs and involution forms are common. 



370. BACILLUS ALBUS PUTIDUS (De Bary). 



Found in water. 



Morphology. Small bacilli, which grow out into filaments. 



Biological Characters. An aerobic, liquefying, motile bacillus. Spore 

 formation not observed. Grows rapidly at the room temperature. Upon 

 gelatin plates forms thin, round colonies upon the surface, which under a 

 low power are light-brown in color and are surrounded by a transparent 

 aureole which at the end of four days has a diameter of five millimetres. In 

 gelatin stick cultures development occurs both on the surface and along the 

 line of puncture, producing rapid liquefaction of the gelatin; gelatin cul- 

 tures give off an intense and disagreeable odor, like that of liquid manure. 

 Upon the surface of agar a smeary layer is developed. Upon potato a 

 slimy growth. 



371. BACILLUS BRASSic^E (Pommer). 



Obtained from an infusion of cabbage leaves. 



Morphology. Bacilli from 1.9 to 5.4/t Iongand0.91 tol 2 p thick; differ 

 greatly in different culture media, forming sometimes twisted and tangled 

 filaments, often spiral in form, and producing at times a network similar to 

 that of Bacterium Zopfii ; the filaments are often segmented and slightly 

 notched and bent at the points where the segments join. 



Biological Characters. Anaerobic and facultative anaerobic, liquefy- 

 ing, non-motile bacillus. Forms spores. Grows in the usual culture media 

 at the room temperature. Upon gelatin plates forms colonies which resem- 

 ble the mycelium of a mucor and cause liquefaction of the gelatin. In gela- 

 tin stick cultures a branching, mycelial-like growth is seen along the line 

 of puncture, in funnel form, and liquefaction of the gelatin quickly occurs. 

 Upon the surface of agar a layer is formed consisting of spots surrounded 

 by a dull cloudy appearance ; later these have a whitish or yellowish color ; 

 under the microscope they are seen to consist of closely lying parallel fila- 

 ments, which may run in a straight or serpentine direction, or may form 

 circular and ellipsoidal figures. Along the line of puncture in agar cultures 

 small, white colonies are developed, which are seen under the microscope to 

 be made up of a confused mass of straight or curved, short filaments, and a 

 network of filaments is given off from these. 



372. BACILLUS BUTYRICUS OF HUEPPE. 



Found in imperfectly sterilized milk. 



Morphology. Bacilli, often slightly curved, about 2.1 ft long and 0.38 M 

 thick ; may grow out into filaments. 



Biological Characters. An aerobic and facultative anaerobic, liquefy- 

 ing, actively motile bacillus. Forms, at 30 C., oval spores which are lo- 

 cated in the centre of the rods. Grows at the room temperature more rap- 

 idly at 35 to 40 C. Upon gelatin plates deep-lying colonies of yellow 

 color are developed, which cause rapid liquefaction of the gelatin and unite 

 into coarsely granular, brown masses. In gelatin stick cultures liquefaction 

 rapidly occurs along the entire line of puncture ; upon the surface of the 



