BACTERIAL CONTAMINATION OF NORMAL MILK. 



37 



in the milk is very much reduced, and frequently the milk at 

 the end of the milking is nearly or quite sterile. There is 



FIG. 10. 



A cow's udder cut across and showing the milk ducts. 



a constant, though not a regular, reduction in the number 

 of bacteria from the beginning of the milking to the end. 

 The presence of the bacteria in these milk ducts is also dem- 



