102 THE AMERICAN MONTHLY [March 



JiACTERlOLOGY. 



Cheese Curd Inflation its Relation to the Bacterial 

 Flora of Foremilk. II. L. P.ollev and C. M. Hall, use the 

 word "foremilk"' to mean the milk from the lirst part of 

 a milking-, not colostrum. Some studies were made on the 

 formation of "pin-holes" in curds which indicated it to be 

 due to the action of l)acteria. "Experienced cheese 

 makers have quite g-enerally affirmed that its chief orig"in 

 is dirty milk." The work upon which this paper is based 

 reaffirms this belief." Preliminary cheese curd and fer- 

 mentation tests were made at two different times with the 

 milk of two cows, using-fhe milk drawn first, thestrippings, 

 and the mixed milk of the whole milking. "The evidence 

 from these tests is that the gas-originating org^anisms 

 were not located in the udders either in the fore or last 

 milk and that the few •j)in-holes' of the curds must have 

 had an external origin." 



Studies were then made of the liacterial fiora of the milk 

 of 10 healthy cows, living under healthy stable conditions, 

 from January 22 to April 25. In each, samples were taken 

 of the first and last milk of the milking- by means of a ster- 

 ile silver milking tube inserted well uj) into the milk cis- 

 tern. xVs a result, 16 distinct species of bacteria were iso- 

 lated, some (jf which were common to both the first and 

 last milk, and others to only one of these. All the micro- 

 organisms found were bacteria, and none were found 

 which produced gfas. "The work is g-iven as a prelimin- 

 arv study, and may be said to indicate — (li no bacterial 

 fiora common to the animals investigated, save one pecu- 

 liar non-milk affecting species; (2) that a given form when 

 once present may be quite constant in its occupancy of 

 the udder of an individual animal. Finally, the absence 

 of gas-producing organisms remains unexplained, but adds 

 sig-nificance to the j^reviouslv described curd tests." 



The Constancy of the Kinds of Bacteriain Normal Milk. 

 — H. L. Bolley made, during tiie summer, cultures of the 

 milk drawn from each teat of three cows. The samples of 



