1This investigation was supported by a research grant from the National Institutes of Health of the Public Health Service.
2Contribution No. 1016 of the University of Massachusetts College of Agriculture Experiment Station.
3Presented at the 42nd annual meeting of the International Association of Milk and Food Sanitarians, Inc., at Augusta, Georgia, October 2–6, 1955.
Ralston B. Read, Jr. was graduated from Brown University in 1946 and received his M.S. degree from the University of New Hampshire in 1950. He is presently the Lotta Crabtree fellow at the University of Massachusetts where he will receive the Ph. D. degree in bacteriology next June. He has served as an instructor at Westbrook Junior College and as bacteriologist in the Division of Communicable Diseases and Tuberculosis of the United States Public Health Service.