—For the past four years this review of congenital deformities has recorded additional contributions to this puzzling subject by Josef Warkany.23 He points out that congenital malformations represent an important pediatric problem also, since they are a notable factor in infant mortality and in children's morbidity. Genetic, infectious and actinic factors have been proved to be etiologic principles leading to malformations. He has also shown that malnutrition of the embryo can be an etiologic factor.It has been observed that animals fed poor diets gave birth to blind young. Warkany raised female rats on a highly purified diet free of carotene and vitamin A. The few rats able to terminate pregnancy produced young which were born blind and had deformed eyes. This is due to an arrest of development in an early embryonic stage. If vitamin A is added to the maternal diet, these deformities are not observed.