Among the most fascinating problems in the study of infectious diseases are variations in virulence. To the physician, the microbiologist and the epidemiologist each new contribution to the study of microbic variation holds out the encouragement that perhaps the veils behind which the mysteries hide will be parted a little wider. But little more than disappointment comes from an examination of this newest monograph. Beginning essentially where Gurney Dixon left off nearly ten years ago, the author presents an analysis of variations in certain cultures of bacteria—particularly of variations associated with fermentation characteristics—which adds little of probable importance or permanent worth.
By a series of ingenious arguments, the author demonstrates that certain variations in culture may be described by assuming that the variant characteristics are determined by multiple allelomorphs. He then proceeds to the experimental "demonstration" of segregation and perhaps autogamic conjugation, and concludes by deducing a probable "life history"