XON-PATHOGENIC BACILLI. 621 



occurs chiefly along the line of puncture ; upon the surface a milk-white, 

 slimy growth is seen about the point of puncture ; this becomes about one 

 millimetre thick and changes to a gray color, while a brown pigment is 

 given off from its lower surface and also along the line of inoculation. 



240. BACILLUS AUREUS (Adametz). 



Found in water and also upon the surface of the body in cases of eczema 

 seborrhceicum by Unna and Tommasoli. 



Morphology. Slender bacilli, straight or slightly curved, from 1.5 to 4 n 

 long and 0.5 /f broad ; often arranged in groups in which the bacilli lie paral- 

 lel to each other; frequently in pairs or in long filaments. 



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

 chromogenic bacillus. Forms a golden-yellow pigment. Spore production 

 not observed. Grows slowly at the room temperature in the usual culture 

 media. Upon gelatin plates forms small superficial colonies of irregular 

 form, which at the end of eight days still appear as small white points ; these 

 later become pale-yellow and finally chrome-yellow in color ; they are opaque, 

 have well-defined outlines, and may attain a diameter of one to four milli- 

 metres; they vary in form, being round or elliptical, and later sometimes 

 sausage-shaped. In gelatin stick cultures development occurs slowly upon 

 the surface in the form of small, hemispherical colonies crowded together to 

 form an irregular, dull-shining, dark chrome-yellow layer ; very scanty 

 growth occurs along the line of puncture. Upon potato broad, glistening, 

 hemispherical colonies are formed, which gradually become confluent and 

 form a dark chrome-yellow layer which in old cultures acquires a deep red- 

 dish-brown color. 



241. BACILLUS FLAVOCORIACEUS (Eisenberg). 



Synonym. Sulphur-yellow bacillus (Adametz). 



Found in water. 



Morphology. Very small bacilli. 



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

 mogenic bacillus. Produces a sulphur-yellow pigment. Spore formation 

 not observed. Grows at the room temperature. Upon gelatin plates forms 

 small, round, sulphur-yellow colonies, which under a low power are seen to 

 be coarsely granular and have a brownish-yellow centre surrounded by a 

 pale-yellow marginal zone ; older colonies are irregular in outline. In gela- 

 tin stick cultures a scanty, granular, grape-like growth occurs on the sur- 

 face and along the line of puncture. 



242. BACILLUS BEROLINENSIS INDICUS (Classen). 



Found in water of the Spree. 



Morphology. Slender bacilli with round ends, resembling the typhoid 

 bacillus in form and dimensions ; usually solitary, sometimes united in pairs 

 or in chains of three. The rods are surrounded by a delicate, transparent 

 envelope. 



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

 genic bacillus. Forms an indigo-blue pigment which is insoluble in water, 

 alcohol, or chloroform, soluble in cold concentrated hydrochloric acid ; is 

 decolorized by ammonia. Spore formation not demonstrated. Grows rap- 

 idly at the room temperature in the usual culture media. Upon gelatin 

 plates, at the end of three days, grayish-white colonies the size of a pin's 

 head are developed ; by the fourth day these commence to acquire an indigo- 

 blue color, the deep colonies around the margin and the superficial colonies 

 more in the centre ; the uncolored margins of the superficial colonies are ir- 

 regularly bulged and have a pearly lustre. In gelatin stick cultures a small, 

 indigo-blue mass develops at the point of puncture at the end of twenty- 



52 



