DAIRY FARMING DAIRYING. 177 



cultures of the typhoid germs, and at the same time with either a culture of 

 B. bulgaricus or B. lactis acidi, which had been recently isolated from sour 

 milk. 



As a result of the work it is concluded that the repressing influence of both 

 the ordinary lactic organism and the organism of Metchnikoff upon the growth 

 of typhoid bacilli in milk, if it occurs at all, is so slight as to be of no signifi- 

 cance, and these organisms can not be depended upon for rendering safe milk 

 which has been inoculated with typhoid fever germs. 



The selective action of media on organisms of the coli group, and its 

 bearing on the question of variation in general, C. Revis (Centbl. Bakt. 

 [etcl, 2. AM., 33 {1912), No. 17-19, pp. J,07-428) .—These experiments were 

 made with milk in all cases except one. Ordinary milk was taken about 12 

 hours after milking and kept for IS or 24 hours at a temperature of 20° C. and 

 then examined, or else the milk was immediately examined and then kept for 

 the necessary lime and re-examined. One experiment was carrie<l out with 

 cow dung freshly excreted, and with a water dilution of it keirt for 1 week at 

 20°. In all cases dilutions by tens were made down to 1 : 10°. One cc. of 

 each after careful mixing was inoculated into tubes of bile salt glucose peptone 

 water, and incubated for 18 to 24 hours at 37.5° anaerobically. 



The results showed that the most numerous form is an organism coagulating 

 milk and attacking lactose, saccharose, and adonitol vigorously. The other 

 organism isolated on the same plate was evidently of the same variety, but 

 much weaker in activity as the full fermentative power was not developed 

 before 72 hours, whereas the other had exhibited its full effect in 24 hours. 

 The results of the different forms are given, followed by a. discussion of 

 variation. 



The following conclusions are drawn : " The types of coli-form organisms 

 which appear on inoculation of dilutions of milk, etc., into bile salt glucose 

 tubes are the result of a combination of mutual toxic action, acid development, 

 and the nature of the medium. There is undoubted suppression of feeble 

 organisms, particularly of those which can only produce acid and not gas from 

 glucose. 



"The aspect which at present obtains of the varieties of 'coli-form' organ- 

 isms is an aspect determined by our media and its concomitants. Atypical 

 forms of 'coli' are not degenerate forms, but stages in the variation of organ- 

 isms belonging to the ' coli-typhoid ' group." 



A study of thirty-five strains of streptococci isolated from samples of 

 milk, G. F. Ruediger (Anier. Jour. Puh. Health, 2 {1912), No. 2, pp. 107- 

 109). — The cultural and morphological characters of streptococci isolated from 

 fresh milk are presented in tabular form, and the following conclusions are 

 drawn : 



" Streptococcus lacticus can be differentiated from S. pyogenes by means 

 of blood agar plates. The latter produces small colonies surrounded by a large 

 zone of hemolysis, whereas the former produces green or greenish colonies with 

 little or no hemolysis. S. lacticus has no sanitary significance as it is found in 

 nearly all samples of clean, soured and fresh milk, and very often in the 

 healthy milk ducts. 8. pyogenes seems to occur but rarely in milk and is indic- 

 ative of the existence of an inflamed condition of the udder of the cow. It 

 seems likely, however, that these organisms may persist for some time after the 

 inflammation has subsided, and that they may occur in mild inflammatory con- 

 ditions." 



An epidemic of septic sore throat in Baltimore and its relation to a milk 

 supply, L. P. Hambukgeb {Jour. Amer. Med. Assoc, 58 {1912), No. 15, pp. 



