DESCRIPTION OF SPECIES 



401 



smeared with butter — small, dr>', 

 white colonies, soon assuming an 

 orange tint and becoming confluent. 



Milk — No coagulation ; forma- 

 tion of reddish-yellow surface ring. 



Potato — Whitish to bright orange 

 growth with some elevation ; dull, 

 dry, wrinkled, not glistening. 



Blood serum — Poor growth ; a 

 thin greyish layer after a month. 



Aerobic. 



Cultures contain a fatt)' sub- 

 stance. Treated with Flemming's 

 solution, they take a black tint. 



Pathogenesis — Rabbits and white 

 mice are immune. In guinea-pigs 

 nodules are found in peritoneum, 

 mesenter\', liver, and spleen. 

 Mesenteric glands though swollen 

 do not usually become caseous. 

 The bacillus is found to be most 

 numerous in glands and nodules, 

 but it is scarce in the blood. Pure 

 cultures are less virulent than 

 butter containing the bacillus. The 

 lesions have a tendency to heal. 

 Giant cells, epithelioid cells, and 

 caseation are generally absent. 



BUTTER BACILLUS (Binot). 

 Source and habitat — Butter. 



Morphology — Bacillus ; like tubercle 



bacillus. 

 Grouping — Like the tubercle bacillus. 



Staining reaction — Acid-fast. Ziehl- 

 Neelsen and Ehrlich stains. 



Motility — No motility observed. 



Spore formation — None observed. 



Biology : cultural characters {includ- 

 ing biochemical features) — Grows at 

 ordinary room temperature, but 

 more rapidly at 37° C. 



Bouillon — A thin friable veil is 

 formed of a pale yellowish colour ; 

 no deposit. Very slight turbidity : 

 thick viscous creamy veil is pro- 

 duced in glycerine bouillon. Stalac- 



tite growth in the bouillon ; becomes 

 orange colour in a few weeks. 



Gelatine plates and tubes — Grey 

 white colonies ; thin, opaque, and 

 creamy; surface irregular. There 

 is no liquefaction of the gelatine. 



Glycerine-agar plates and tubes 

 — White colonies becoming straw- 

 coloured, finally orange. May 

 attain diameter of two franc-piece 

 or larger ; bright glistening sur- 

 face ; very adherent to medium ; no 

 growth in depth of medium ; sur- 

 face soon becomes wrinkled, with 

 scalloped edges (Plate 25, p. 256). 

 Chromogenic characters more 

 marked if growth exposed to air 

 and light. Stroke cultures show 

 same character. On ordinary agar 

 colonies similar, but less luxuriant. 

 Potato — Scanty growth, at first 

 moist ; clear yellow colour, becom- 

 ing "farineuse" with age. On 

 glycerine potato an abundant 

 homogeneous growth occurs ; 

 opaque, yellow, turning to orange ; 

 irregular nodosities appear on the 

 colony. 

 Aerobic. 



Vitality — Considerable. 

 Pathogenesis — Binot inoculated 

 a guinea-pig in March 1899 with 

 the butter bacillus. The animal 

 died spontaneously, slightly emaci- 

 ated, at the end of 29 days, 

 having the following post-mortem 

 characters : — On post - mortem 

 examination the viscera of this 

 animal were found to be of nor- 

 mal size and aspect, with the 

 exception of the spleen, which was 

 slightly enlarged. The liver and 

 the spleen were, however, found to 

 be studded throughout with fine 

 miliary granulations of the size of 

 a small pin's head, and of a yellow- 

 ish-white colour, recalling vaguely 

 those found in cocco-bacilliary 

 tuberculosis. In the peritoneum 

 2 C 



