102 THE AMERICAN MONTHLY [March 



BACTERIOLOGY. 



Cheese Curd Inflation — its Relation to the Bacterial 

 Flora of Foremilk.— H. L. Bolley and C. M. Hall, use the 

 word "foremilk" to mean the milk from the first 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 bacteria. "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-themilkdrawn first, thestripping-s, 

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

 from these tests is that the g-as-orig-inating org-anisms 

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

 milk and that the few 'pin-holes' of the curds must have 

 had an external orig-in." 



Studies were then made of the bacterial flora 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 up into the milk cis- 

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

 lated, some of which were common to both the first and 

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

 org-anisms found were bacteria, and none were found 

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

 ary study, and may be said to indicate — (1) no bacterial 

 flora common to the animals investig-ated, save one pecu- 

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

 once present may be quite constant in its occupancy of 

 the udder of an individual animal. Finally, the absence 

 of g-as-p rod ucing- org-anisms remains unexplained, but adds 

 sig-nificance to the previously described curd tests." 



The Constancy of the Kinds of Bacteriain Normal Milk. 

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

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



