I ? ADDENDUM 



streptococci derived from the horse, sheep, rabbit (wild) and 

 gull were lactose positive that these animals might almost 

 be excluded from further consideration." A gross total of 296 

 subcultures yielded only four positives. As regards any satis- 

 factory differentiation Houston remarks that the results were 

 disappointing. 



Broadhurst studied 100 milk streptococci all obtained from 

 mixed milk samples. These strains fell into 20 groups classified 

 on the basis of their ferment activities. As regards the extent 

 to which the individual substances were fermented she obtained 

 the following results : salicin 82, lactose 76, saccharose 66, 

 inulin 38, raffinose 13, mannite 27 per cent. She concluded 

 that the milk streptococci are characterised by unusually high 

 fermentative powers, and that they resemble human rather than 

 bovine strains, and show practically no resemblance to the 

 equine strains. 



Broadhurst in a later paper studied the characters of 767 

 strains, all but 23 being freshly isolated for the purpose. Her 

 careful and prolonged investigations must be studied in the 

 original and cannot be conveniently summarised, but in general 

 her work affords confirmation of the view that the differentiating 

 characters employed are insufficient to indicate the origin of a 

 particular strain and that great caution must be used in using them 

 for direct sanitary application. Interesting points amongst her 

 results were that by all methods human throat strains practically 

 failed to ferment mannite while in human faeces mannite strains 

 were common. Rafifinose fermenters were more prominent in 

 bovine faeces than in the faeces of other animals, while they 

 were strikingly lacking in milk. Many of the strains from 

 pathological sources failed to ferment raffinose and mannite. 



The separate papers must be studied to see the actual 

 fermentation properties of the individual streptococci. Lactose, 

 saccharose, raffinose, mannite, inulin and salicin would all appear 

 to have some differentiating value, but some observers would 

 omit saccharose as fermented by nearly all strains, others 

 mannite as fermented by too few, while Houston in his last 

 investigation found salicin of no value in his attempt to 

 differentiate human and animal excretal streptococci. 



