872 EXPERIMENT STATION RECORD. * 



rarely If ever in certified. It is thought that the presence of this organism, 3 to 

 4 per cubic centimeter, is an indication of contamination. It is said that a 

 high spore count in a pasteurized milk indicates either a poor raw milk, a low 

 pasteurizing temperature, or contamination with heat-resisting forms after 

 pasteurization. Certified milk and good inspected milk had .surprisingly few 

 spore forms. 



The rate at which colonies on agar plates incubated at 21° C. develop may 

 be used to differentiate different grades of milk, being more rapid in the raw 

 than in the pasteurized or certified milks. 



In a stiidy of the curd produced by milks of the various clas-ses at 37° it 

 was found that raw and pasteurized milks all promptly formed lactic acid 

 curds, while the inspected and certified milks more frequently formed sweet 

 or gaseous curds. 



A number of milks were heavily seeded with Bacillus coli and then pas- 

 teurized at 60° for 20 minutes. By this procedure it was found impossible 

 always to kill all of the B. coli present. 



Bacteriological inquiry on sterile milk sold in Brussels, H. Kuffebath 

 (Ann. Gembloux, 24 (1914), ^o. S, pp. 411-424; a&s. in Intermit. Inst. Agr. 

 [Rome], Mo. Bui. Agr. Intel, and Plant Diseases. 5 {1914), No. 11, p. 1511).— 

 From his observations the author concludes that the maximum limit for the 

 number of bacteria allowable in sterile milk should be about 50,000 per cubic 

 centimeter, estimated by counts on gelatin plates kept for three days at a tem- 

 perature of 88° C. At the same time no injurious bacilli such as coli and 

 tuberculosis forms must be allowed. 



Relation of the number of Streptococcus lacticus to the amount of acid 

 formed in milk and cream, P. G. Heinemann (Jour. Infect. Diseases, 16 (1915), 

 No. 2, pp. 285-291. fig. 1). — From his study the author concludes that "the 

 amount of acid formed in the souring process of milk or cream is not dependent 

 solely on a definite number of bacteria of the S. lacticus group. Temperature 

 and the presence of other bacteria may Influence the result. In raw milk or 

 cream, or in raw milk or cream inoculated with cultures of the S. lacticus, the 

 number of bacteria increases to a given point and then decreases. At 37° C. 

 the maximum is reached after 24 hours and at lower temperature after several 

 days. 



" Coagulation of milk or cream is not solely dependent on a definite amount 

 of acid or a definite number of bacteria. This absence of definite relation 

 between coagulation, on the one hand, and acid and number of bacteria, on the 

 other hand, may be due to the kinds of bacteria present, the kind of acid 

 formed, and the activity of the enzyms produced by bacteria. At 37° extraor- 

 dinarily high amounts of acid may be produced after several days, due probably 

 to the activity of enzyms produced by the S. lacticus and to the presence of 

 members of the group of lacto bacilli." 



Milk poisoning' due to a type of Staphylococcus albus occurring in the 

 udder of a healthy cow, M. A. Barber (Philippine Jour. Sci.. Sect. B, 9 (1914), 

 No. 6, pp. 515-519). — This is an account of milk poisoning in the Philippine 

 Islands, where acute attacks of gastroenteritis were produced by a toxin elab- 

 orated by a white staphylococcus which occurred in almost pure culture in 

 the udder of a cow. Tlie fresh milk was harmless, and the toxin was produced in 

 effective quantities only after the milk had stood some hours at room tempera- 

 ture. Culturally the toxin-producing staphylococcus differed little from a 

 nontoxln-producing strain, except that the former produced acid in mannite 

 and maltose agars. 



It is said that "cnses of gastroenteritis occurring in the Tropics and in the 

 warm season elsewhere may be due to a toxin of similar origin, especially' 



