in five days, whereas plates incubated at 37 degrees required ten days before the original count was reached. A marked difference in the bacterial counts appears in the next few days on the plates incubated at 20 degrees C. On the seventh day on the plates incubated at 20 degrees the count is 11,700, on the eighth 73,000, ninth 650,000, tenth 7,600,000. eleventh day 25,000,000. If we now compare the bacterial counts of the same sample kept at the same temperature for the same length of time we note a marked difference in the number of organisms developing at 37 degrees C. For instance, on the eleventh day, plates incubated at 37 degrees gave a count of 16,500, while the 20 plates gave a count of 25,000,000. This observation seems to us very important. It indicates that milk kept on ice at a temperature of 0.5 to 3.0-C. for a certain length of time requires for the determination of its bacterial content not plates incubated at 37 degrees but plates incubated at a distinctly lower temperature. The exact cause of this wide difference in bacterial count we are not willing at present to suggest, but we do believe that counts made of milk kept for a considerable length of time at a low temperature do not indicate the number of bacteria present when the plates are incubated at 37 degrees C. We have isolated an organism which we think gives rise to this sudden increase in the number of colonies developing on the 20 plates which has the following cultural characteristics: Colonies on agar plates-large, round, white, glistening; agar streak-thin grayish moist growth, slightly elevated; litmus milk-primary acidity, returning alkaline; gelatin liquefied rather rapidly; potato-abundant brownish cream-tinted growth; glucose agarno gas. Morphology-short rod, .4-.7 x 1.1 u. Gram. negative. These cultural characteristics correspond very closely with Bact. desidiosum described by Chester. The most striking characteristic of this organism as far as our investigation goes is that it grows luxuriantly at twenty degrees but refuses to grow at thirty-seven degrees Centigrade. The acidity of the milk showed only slight variations during the first two weeks. With this sample there was an initial acidity of 1.4% N/I HCI (.126% lactic acid) and at 14 days the acidity was 1.7% N/I HCI (.153% lactic acid). After this the acidity increased rapidly and at the end of thirty-two days reached 5% N/I HCI (.45% lactic acid). What practical bearing do these bacterial counts have? In the first place to determine with more or less accuracy the number of bacteria in milk kept at a low temperature for a certain length of time plates should be incubated at 20 degrees rather than 37 degrees. We are aware of certain instances where milk was carried packed in ice on a journey of a week or more. At the end of this time bacterial counts were made, plates being incubated at 37 degrees, and no material increase in the number of organisms being noted. If, however, the incubation had been made at 20 degrees a distinct increase would have been evident. The results of this investigation may have some bearing on certain cases of ice cream poisoning. It has been maintained that if milk be kept at a temperature of 0 degrees C. or below, that no increase in the number of bacteria will occur. Ice cream, containing a certain amount of dissolved solids, requires a rather low freezing point, and it is possible that in keeping cream frozen the bacteria will not increase. It is a well known fact that in the commercial manufacture of ice cream it is a practice to collect unused ice cream and again freeze it. The temperature of the melted cream is most likely around or slightly above 0 degrees C.-the temperature at which our samples were kept, and it is possible that an enormous increase in the number of bacteria takes place. We have already noted that the organism which gives rise to the sudden increase on the 20 degrees plates refuses to grow at 37 degrees. We have not yet shown however, that it is destroyed at 37 degrees. If this be the case, could the causes of certain cases of ice cream poisoning be ascribed to the destruction of enormous numbers of these organisms in the human body? The interesting observation was also made that Certified Milk may be kept wholesome as long as fourteen days. In some instances coagulation had not occurred after thirty days. Bibliography Ztschr. f. Hyg., 1890, 9, p 41. New York Univ. Bull. Med. Sc., 1901, p 2. Milch-hydrenische Unt. Jena. 1904. Jahrbuch fur Kinderheilkunde, 1905, 2, p 365. Ztschr. f. Hyg., 1895, 23, p 170. Ztschr. f. Hyg., 1893, 13, p 336. Journal Infect. Diseases, 1908, No. 5. Journal Infect. Diseases, 1907, No. 4. The Lancet, 1907, vol. 2, p 1074. Constitution and By-Laws of the American Association of Medical Milk Commissions CONSTITUTION Article I. Name of the Association The name of this organization shall be "The American Association of Medical Milk Commissions." Article II. Purposes of the Organization The purpose of this Association shall be: (1) to federate and to bring into one compact Association the Medical Milk Commissions of the United States; (2) to exchange views, and to adopt uniform methods of procedure in the work of the Medical Milk Commissions; (3) to fix chemical and bacteriologic standards; (4) to determine the scope of medical and veterinary inspections, and (5) to foster and encourage the establishment of Medical Milk Commissions. Article III. Membership Section 1. Any Medical Milk Commission, on nomination of Council, may become a member of the Association on twothirds vote of the registered members present at any regular meeting, and on payment of the dues for the current year as prescribed by the Council. Sec. 2. Any individual especially interested in dairy hygiene, not a member of a component Medical Milk Commission, on recommendation of the Council, may become an individual member by a majority vote of the registered members at any meeting, and by paying such dues as the Council may prescribe. Members of component Medical Milk Commissions in good standing may become individual members of the Association by paying such dues as the Council may prescribe. Article IV. Composition of the Conferences of this Association Section 1. The Conferences shall include delegates, individual members, and guests. Article V. Sessions and Meetings Section 1. The Association shall hold an annual session at a time and place to be fixed by the Council. Section 1. The officers of this Association shall be a President, a Secretary, an Assistant Secretary and a Treasurer. Sec. 2. The officers shall be elected for a term of one year, and shall serve until their successors are elected and installed. Sec. 3. The Council shall be composed of the officers of the Association and five additional members. Each year one of the members of the Association shall be elected to Council for a term of five years. At each annual meeting the member of the Council who has served the longest as a member shall be Chairman. Sec. 4. The officers of the Association and members of the Council shall be elected by vote of the Association (delegates and individual members). Article VII. Duties of Officers Section 1. The President.-It shall be the duty of the President to preside at all meetings of the Association. Sec. 2. The Secretary.-The Secretary shall conduct all correspondence of the Association; shall arrange the details of the |