404 DESCRIPTION OF SOME SPECIES OF MILK BACTERIA 



In old cultures the deposit becomes 

 more voluminous and, when the 

 tube is shaken at times, rises in the 

 form of column -like filaments. The 

 veil becomes thicker, wrinkled, of 

 a yellowish colour, and creeps along 

 the walls of the tube. The liquid 

 remains clear and without odour. 



Agar stab — Growth abundant ; 

 yellow and wrinkled on the surface 

 of the medium ; very rare growth 

 on the needle track. 



Glycerine-agar stroke culture — 

 On the second day fine white 

 growth commences on the needle 

 track ; after from 4 to 6 days the 

 culture becomes of a deep yellow 

 colour, moist, fatty, shining, with 

 raised edges and much wrinkling 

 on the surface. At the end of from 

 I to 2 months the tint passes to 

 orange, the folds or wrinkles be- 

 come more marked and especially 

 more numerous ; the culture remains 

 moist and is well raised above the 

 surface of the medium. In the 

 rare cases in which the chromo- 

 genic property is lacking, the 

 isolated colonies are round and 

 dull in the centre with clear edges; 

 the centre of the colony is umbilical. 



Gelatine — Growth very slow and 

 poor. No wrinkling ; yellowish 

 white colour which turns to a 

 brownish tint in old cultures. No 

 liquefaction. 



Potato — A greyish white humid 

 growth turning later to a yellowish 

 orange and becoming wrinkled. 



Milk — Is not coagulated. 



Blood serum — A yellowish humid 

 growth with fine edges and no 

 wrinkling, it does not extend 

 beyond the surface of the medium. 



Pathogenic properties — The in- 

 traperitoneal injection of a large 

 quantity of pure culture leads, at 

 the end of a few days, to a general- 

 ised infection, with invasion of the 



bacilli into the blood and organs, 

 followed rapidly by death. Sub- 

 cutaneous injection of a pure culture 

 gives rise to local abscess, with pas- 

 sage of the bacilli into adjacent 

 glands. A simultaneous injection 

 of pure culture and sterilised butter 

 gives rise to peritonitis, and a strong 

 general reaction, with invasion of 

 the bacilli into the blood, and death 

 within from 4 to 6 days. 



Maria Tobler has never found 

 giant cells in any of the lesions 

 caused by this organism. She is 

 of opinion that it presents a strong 

 general resemblance to the Grass- 

 bacillus, No. 2, of Moeller, but she 

 has never observed the ramifications 

 which Moeller gives as character- 

 istic of his bacillus. 



BUTTER BACILLUS, No. 2 (Tobler). 



Source and habitat — Zurich butter. 



Morphology — Morphologically re- 

 sembles B. tuberculosis. The 

 bacilli are of variable length and 

 breadth. In cultures upon agar of 

 from 2 to 3 weeks growth filaments 

 found, but the filaments are not 

 ramified ; the organism is present 

 also in club form. 



Staining reaction — The organism is 

 less resistant to decolorisation by 

 acids than the bacillus. No. i, when 

 stained by the method of Ziehl- 

 Neelsen. In sections its resistance 

 to acids is very feeble. Stains by 

 Gram's method. 



Spores and motility — Absent. 



Biology : cultural characters — Growth 

 is rapid and abundant upon all 

 ordinary media at 37° C, cultures 

 becoming visible at the end of 

 24 hours ; it grows at room tem- 

 perature and more quickly than 

 the bacillus. No. i. 

 V Agar — A wrinkled humid growth 

 which becomes dry at the end of a 

 few weeks, and takes a brownish tint. 



