FAILURE of development of structures in the brain derived from the lamina terminalis, usually reported under the title of "agenesis of the corpus callosum," is an uncommon but well known condiition. Its chief interest in the past has been in connection with studies of the embryology and function of the corpus callosum and as a minor cause of mental deficiency in human beings. Definite etiologic agents have not been proved, although various infections, toxins and mechanical factors have been suggested. Aside from the failure of development of other structures derived from the lamina terminalis, such as the anterior commissure and the hippocampal commissure, these patients usually have one or more additional cerebral anomalies but rarely any extracranial defects, and usually they have good physical development.1 We have found no reports of agenesis of the corpus callosum associated with cataracts.
The case to be described differs from the usual picture