in THE BACTERIA FOUND IN MILK 41 



gramme of moist excreta were recorded. It is also commonly 

 present in dust. 



Its essential characters, as described by Klein/ are given 

 in the following table : 



I. 



B, hutyncus. 



1. Cylindrical rods, on 

 the average 2 '5 to 3 "5 

 fi long, 0-8 to 1-26 fi 

 broad ; stains well by- 

 Gram's method'; some 

 individuals motile. 



2. Spores oval ; stain after 

 the several methods ; 

 situated in the middle 

 of the rods more or less. 



3. Grows well on the sur- 

 face of ordinary gelatine 

 as a translucent mass of 

 convoluted threads ; 

 does not liquefy the 

 gelatine. 



4. In stab in gelatine, 

 forms spherical colonies 

 with numerous hori- 

 zontal filamentous pro- 

 jections; notliquefying; 

 forms much gas. 



5. On the surface of agar, 

 grey, round, flat colon- 

 ies ; margin thin and 

 muchcrenate; nospores. 



6. In stab in agar, forms 

 characteristic bundles 

 of tlireads projecting 

 laterallyfiom the growth 

 in the stab ; much gas ; 

 no spores. 



7. In milk, rapid separa- 

 tion of acid whey and 

 iloeouli of casein ; smell 

 of butyric acid ; no 

 spores ; much gas. 



8. Grows well on serum ; 

 very slow softening. 



9. Not pathogenic for 

 rodents. 



II. 



B. cnteriiidis sporogtnr. 



1. Same as in I. 



2. Same as in I. 



3. Softens rapidly the 

 gelatine ; slowly 

 liquefying. 



4. Much gas; spherical 

 colonies; without 

 filamentous projec- 

 tions ; slowly lique- 

 fying- 



5. Same as in I. ; few 

 crenations; no 

 spores. 



!. Little tendency for 

 forming lateral 

 branchings ; m u c h 

 gas ; no spores. 



'. Same as in I. 



8. Grows well ; slowly 

 liquefying ; some 

 spores formed. 



9, Virulent for rodents. 



III. 



B. cadodriis sporogenp.s. 



1 . Cylindrical and thread- 

 like; thinner and longer 

 than I. and TI. ; very 

 motile ; stains by Gram's 

 method. 



2. Spores oval, terminal, 

 drumsticks ; stain after 

 usual methods. 



3. Rapidly liquefying ; 

 putrid odour ; numer- 

 ous spores formed. 



4. Much gas ; rapidly 

 liquefying ; putrid 

 odour. 



. On the surface of agar 

 forms thready, branched 

 colonies, with or with- 

 out finely granular 

 plate ; rapidly forming 

 spores. 



. Much gas ; rapidly 

 forming spores ; conspic- 

 uous masses of threads 

 growing out of stab. 



7. Milk is slowly deooni' 

 posed ; putrid odour ; 

 much gas ; rapidly 

 forming spores. 



8. Rapidly liquefying ; 

 putrid odour ; rapidly 

 forming spores. 



9. Not pathogenic for 

 rodents. 



The virulence of this organism is subject to considerable 

 variation. When fully virulent 1 c.c. of the whey from a 



1 Jieport of Medical Officer, Local Government Board, 1901-2, p. 404. 



