The possibility that the time of birth might affect the subsequent destiny of the individual is a fascinating concept which, in the "science" of astrology, has been with man for thousands of years. While astrology in contemporary Western civilization is no longer considered a valid avenue of scientific inquiry, medical research in the last 35 years has again made respectable an analogous line of investigation: the relationship between month of birth and the various types of mental illnesses and deficiences. These studies are easily carried out, and with only a few exceptions appear to confirm one another. And yet, in a survey of the literature since 1938, when Huntington4published his book on season of birth, one is struck by the fact that the factorsnotinvestigated are frequently as significant as the relationships the investigators seek to prove. One is forced to conclude that