CONGENITAL malformations, which are not of genetic origin, are now commonly associated with insult and injury to the embryo, usually during the first trimester of pregnancy. However, there are persistent reports throughout the literature which relate certain gross deformities of the fetus to defects in the membranes. Most of these reports are incomplete and represent chance findings. The authors over a period of years have systematically studied some 10,000 fetal membranes. The following case is of interest in that it permits a correlation between the clinical course of a pregnancy and the condition of the membranes and fetus. Report of a Case The mother was multipara 4, 30 years of age, whose previous pregnancies were normal. She came under observation in the third month of pregnancy with a report of spotting during the second month. The history was negative for measles, trauma, and infectious disease. In the sixth month amniotic