496 EXPERIMENT STATION RECORD. 



region of the nucleus. Vacuoles appear later. The fat globules are expelled with- 

 out injury to the cells. While mitosis and eel] degeneration may occur synchro- 

 nously with fat secretion, the latter is n<»t dependenl upon these two processes. 



Nitrogenous substances are found in the large secreted bodies and also in the form 

 of small and large drops in the cytoplasm of the cells and in the alveoli. Colostrum 

 bodies are for the most part derived from leucocytes, in which process both phago- 

 cytosis and synthesis take part. Epithelial cells containing fat are, however, also 

 found in the alveoli. The cap-like appendages of colostrum bodies are of different 

 origin. A bibliography is appended. 



Investigations of market milk in Leipsic with, special reference to the 

 presence of streptococci, H. Bruning {Jahrb. Kinderheilk., 62 (1905), No. 1, pp. 

 1-21).— Forty samples of market milk were collected during the period from July to 

 October, 1904, and examined. 



Of the 26 samples of whole raw milk 7 were amphoteric in reaction and 19 alkaline. 

 Five samples showed a fat content below 2.S per cent, the legal standard in Leipsic. 

 The average of the 26 samples was 3.12 per cent. Storch's reaction for detecting 

 raw milk was positive except in one instance, in which case Schardinger's formalin- 

 methylene blue reaction was also negative. The latter test was negative with goat's 

 milk. 



Streptococci were present in 93 per cent of the samples of raw milk, varying in 

 number from 100 to 1,000,000 per cubic centimeter. The morphological and cultural 

 characteristics of some of the different forms are briefly noted. In one instance the 

 intraperitoneal injection of a mouse with an excessive dose of a bouillon culture of a 

 streptococcus isolated from the milk proved fatal. Otherwise the streptococci iso- 

 lated were nonpathogenic for mice and guinea pigs. 



Extended studies of the associative action of bacteria in the souring of 

 milk, C. E. Marshall (Mich igan Sta. Spec. Bui. 33, pp. 23). — This is a continuation 

 of investigations previously noted (E. S. R., 16, pp. 299 and 1014). 



The history and characteristics are given of the germ designated B, which has 

 been found to hasten the souring of milk when grown in association with lactic- 

 acid bacteria as compared with the time required by the lactic-acid bacteria when 

 grown in pure cultures. The author presents considerable data and discusses at 

 some length the variations in milk in relation to bacterial, development, concluding 

 that this variation is at all times of sufficient importance to be borne in mind when 

 milk is used for cultural purposes. The author has also found that litmus added to 

 milk causes irregularity in cultures as compared with the same lot of milk without 

 litmus. 



The changes produced in milk by germ B, so far as ascertained, are described. In 

 experiments in butter making, it was found necessary to add 45 per cent of a starter 

 of the lactic-acid organism used in order to cover up the disagreeable odor and taste 

 produced in butter by germ B. The importance of associative action in practical 

 dairying is discussed and it is noted that experiments are now in progress to secure 

 more knowledge upon this subject. 



A popular review of Special Bulletin No. 33 on "The associative action of 

 bacteria in the souring of milk," C. E. Marshall (Michigan Sta. Bui. 229, pp. 

 196-201).— See above. 



The bacteria of pasteurized and unpasteurized milk under laboratory con- 

 ditions, L. A. Rogers ( U. S. Dept. Agr., Bur. Anim. Indus. Bui 73, pp. 32).— The 

 author reviews considerable literature on the subject of milk supplies of cities, show- 

 ing thereby that milk is usually found to be badly contaminated by bacteria, and 

 that while some authorities consider pasteurization an advisable remedy for this 

 condition, others believe that the bacteria which develop in pasteurized milk make 

 it more dangerous than raw milk. 



