134 THE ENUMERATION OF BACTERIA IN MILK 



These results show no definite relationship between the 

 acidity and the bacterial count until the acidity approaches 

 0.20 per cent (22°), and in this respect, are confirmatory of 

 Fred's results. Only 9 samples out of a total of 917 exceeded 

 22° acidity and it became obvious that the acidity determina- 

 tion even as a guide to the best dilutions to employ in plate 

 work did not give information commensurate with the labour 

 involved. For pasteurised and heated milk the acidity estima- 

 tion is of even less value than for ordinary raw milk owing to 

 the change in acidity acused by the heating processes. 



BIBLIOGRAPHY 



1. Dellpine. Jour, of Hyg. 1903, 3, 68. 



2. Laboratory Rpt. of Chicago Dept. of Health. 1907-1910. 



3. Race. Can. Jour, of Pub. Health. 1915, 6, 13. 



4. Conn. Pub. Health Rpt. U.S.A.P.H.S., 1915, 30, 2390. 



5. Heinemann and Glenn. Jour. Inf. Dis. 1908, 5, 412. 



6. American Jour, of Pub. Hyg. 18, 431. 



7. Clark. Jour. Inf. Dis. 1915, 17, 109-136. 



8. Slack. Tech. Quart. 1906, 19, No. 1. 



9. Standard Methods for Bact. Exam, of Milk, Amer. Pub. Health. 



Assoc, 1912, p. 25. 



10. Goodrich. Jour. Inf. Dis. 1914, 14, 512. 



11. Breed. Centrabl. f. Bakt., Abt. 2, 30, 337-340. 



12. Skar. Milchw. Zentbl. 41, 454-461, ibid., 705-712. 



13. Rosam. Milchw. Centbl. 1913, 42, 333. ■ 



14. Conn. Pub. Health Rpt. U.S.A.P.H.S. 1915, 30, 2394. 



15. Barthol. Zeit. Untersuch. Nahr. Genussm. 1908, 15, 385-405. 



16. Fred. Zeit. f. Bakt. u. Parasitenk. 1912, 35, Abt. 2, 391. 



17. Fred. Rpt. Virginia Agar. Expt. Sta. 1911-12, 206-240. 



18. Barthol. Zeit. Untersuch. Nahr. u. Genussm. 1911, 21, 513-534. 



