REPORT OF THE SUPERVISING BACTERIOLOGIST. 15 
Report of the Supervising Bacteriologist. 
Lo the Director of the Storrs Agricultural Experiment Station: 
SIR:—I beg to submit the following report of the work done 
under my direction in the Station during the past year. 
The work in dairy bacteriology has consisted of several inde- 
pendent pieces of investigation. 
1. The investigation upon the relation of temperature to 
the types of bacteria that grow in milk, of which a partial report 
was given in the last annual bulletin, has been continued and 
extended. A long series of experiments upon the effect upon 
the same lot of milk of preserving it at various temperatures— 
IT, 10°, 20°, and 30°—has been carried on, and a report of 
these experiments will be found in the following pages. The 
general result has been to show that variations in temperature 
not only greatly affect the rapidity in growth of bacteria in 
milk, but also affect the species which develop. It has been 
found that the temperature favoring the most useful dairy 
species is 20°C. At higher temperatures species grow which 
are unsatisfactory both for butter making and cheese making; 
and at lower temperatures, though the development is much 
slower, the bacteria do develop in time, and there is much 
greater probability that the species which eventually develop 
will injure or ruin the milk, rendering it unwholesome as a 
food. 
2. Experiments which were begun a year ago, upon the 
manufacture of soft cheeses, have been continued and greatly 
extended. In this work the Agricultural Department has 
associated with the Experiment Station. two investigators. Dr. 
Charles Thom, as mycologist, is undertaking the study of the 
fungi connected with the ripening of soft cheeses, and will 
report the outline of the work he has undertaken. Mr. A. W. 
Bosworth, the chemist, is undertaking the solution of some of 
the chemical problems for the ripening of these cheeses, and a 
