492 



SCIENCE. 



[N. S. Vol. XXI. Xo. 535. 



properties of the prodigiosus products with- 

 out lessening their protective action have 

 not given the desired results. 



Associative Action of Bacteria on the Sour- 

 ing of Milk: C. E. Marshall, ]\Iichigan 

 Agricultural College. 

 The author, working with cultures of 

 associated bacteria, consisting of B. acidi 

 lactici, and a bacillus obtained from milk 

 and not yet described, possessing marked 

 proteolytic action in its growth upon milk, 

 and producing alkaline reaction, decidedly 

 marked in old cultures, has been able to 

 demonstrate that loppering is hastened by 

 the presence of this proteolytic germ over 

 that of the lactic acid germ, by as many as 

 ninety-six hours at times, temperature 20° 

 C. ; that the acidity rises high above that 

 of the lactic germ ; that these changes may 

 be noted by the naked eye appearances of 

 the cultures ; and, further, that the lactic 

 acid germ develops much more rapidly 

 when associated Avith these proteolytic 

 germs than when existing in pure cultures. 

 He has also found that' the products pro- 

 duced by the proteolytic germ are stable 

 and that they may exert the same influence 

 as the presence of the living germ. An- 

 alyses of cultures at various ages indicate 

 that the products influencing the growth 

 of the lactic acid germ are either amido 

 or ammonia compounds. Synthetic cul- 

 tural media have been attempted, but with- 

 out satisfactory results thi;s far. 



It may also be said that peculiar curdling 

 effects have been obtained with fresh milk 

 from the cow and of various ages there- 

 after. This may account for certain pe- 

 culiar cultural results secured in cultivat- 

 ing germs in various samples of milk. 



The description of the proteolytic germ 

 and the detailed work will be published in 

 Centralhl. f. Bakteriol, etc' (Zweite Abteil- 

 ung), at no distant date. 



Bacterium truttce: A Pathogen to Trout: 

 M. C. ]\'Iarsh, U. S. Bureau of Fisheries. 

 An organism which causes serious epi- 

 demics among domesticated brook trout 

 and is not pathogenic to warm-blooded ani- 

 mals. The characters of chief interest are 

 its pleomorphism, color production, appa- 

 rent acquirement of motility on media, and 

 low death point. 



(Complete paper in Bulletin of S. 

 Fish Commission, 1902, p. 411.) 



A Germ-proof Filter: F. P. Gorham, 

 Brown Univei"sity. 



The filter consists of a porcelain tube 

 upon w^hieh a layer of aluminum hydrox- 

 ide, bound together by mineral wool, is 

 deposited. The effluent is of excellent 

 quality chemically, all algal odor is re- 

 moved, is germ free after running continu- 

 ously for over a year, and the rapidity of 

 flow is some seven times that of the im- 

 coated tube at the start, and double the 

 speed of flow of an uncoated tube after a 

 continuous run of fourteen days. 



The filter is the invention of Mr. James 

 G. Woolworth, Providence,. E. I. 



The Bacteria Encountered in Suppura- 

 tions: D. H. Bergey, University of 

 Pennsylvania. 



In the examination of pus by the stu- 

 dents in the laboratory it has been my ex- 

 perience that frequently bacteria are en- 

 countered which are not ordinarily classed 

 among the pyogenic organisms. The fre- 

 quency with which certain of these organ- 

 isms w^ere encountered and the fact that 

 some of these organisms had previously 

 been encountered in suppurating wounds: 

 that organisms of a similar character had 

 been encountered in catarrhal mammitis in 

 cows; moreover, the fact that similar or- 

 ganisms have been encountered in abscesses 

 occurring spontaneously in mice, led to the 

 opinion that they might possibly have a 



