DESCRIPTION OF SPECIES 



415 



formation ; colonies in depth are 

 round, white by reflected light, 

 brown and granular in transmitted 

 light. On surface of agar plates 

 flat, circular, moist, grey colonies 

 appear in 24 to 48 hours ; thicker 

 in centre than at margin, and 

 showing granularity. 



Milk — Grows well in milk, pro- 

 ducing the "enteritidis change." 

 After 36 hours of anaerobic incuba- 

 tion at 37' C. in milk, the cream is 

 torn or dissociated by development 

 of gas, so that the surface of the 

 medium is covered with stringy, 

 pinkish-white masses of coagulated 

 casein enclosing a number of gas 

 bubbles. The main portion of the 

 tube of milk contains a colourless, 

 thin, watery whey, with a few casein 

 lumps here and there adhering 

 to the sides of the tube. The 

 whey has a smell of butyric acid, 

 and is acid in reaction. It con- 

 tains many bacilli. 

 Anaerobic. 



Vitality — Considerable. 

 Pathogenesis — If i c.c. of milk 

 whey containing the bacillus be in- 

 jected into a guinea-pig (200 to 300 

 grammes), a swelling appears in 

 6 hours, extending over abdomen 

 and thigh, and death occurs in 

 18 to 24 hours. Post-mortem : 

 subcutaneous gangrene with much 

 sanguineous exudation, in which 

 bacilli and spores will be found. 

 Klein considers this organism the 

 cause of epidemic diarrhoea. 



BACHiliUS FILIPORMIS LACmS 



(Conn). 



Source and habitat — Milk. 

 Morphology — Delicate rods. 

 Staining reaction — Ordinary aniline 



stains. 

 Capsule — A thick capsule with central 



staining matter. 



Spore formation — Spores (1-2 /x by 



1-8 m). 

 Biology : cultured characters {includ- 

 ing biochemical features^ 



Gelatine plates and tubes — Colony 

 with fine granular centre, breaking 

 at its margin and surrounded with 

 clear liquefying zone. Later the 

 margin shows contorted lacing 

 threads. In stab-cultures a narrow 

 funnel of liquefaction is produced ; 

 much gas is produced, appearing 

 as bubbles in liquid and in gelatine. 

 Liquefaction becomes complete and 

 a dense serum and sediment is 

 formed. 



Agar plates and tubes — A thick 

 spreading branching grov^th is 

 generally produced, sometimes thin 

 and dry. 



Potato — A moist yellowish, shiny 

 mass grows over surface. 



Milk — Is curdled in 2 days wth 

 little change in reaction. Cream 

 is rendered slightly acid with a sour 

 cream taste, and butter made there- 

 from has a good flavour but no 

 aroma. 



Aerobic and facultative anaerobic. 



Non-pathogenic. 



Henrici describes another or- 

 ganism under this term. 



BACn.IiUS PLUORBSCBNS LIQUB- 

 PACIENS. 



Source and habitat — Water and air ; 

 thence to milk. 



Morphology J form, dimensions, and 

 manner of grouping — Short rods, 

 about -4 /* in breadth and about 

 1-5 M in length ; on solid media the 

 length is sometimes as much as 

 3-2 ii. ; in media unfavourable for 

 its growth many involution forms 

 appear, curved, in form of cross, 

 or spiral. 



Staining recution — Ordinary stains. 

 By Gram's method decoloration 



