Abstract
The hydrocephalic brain of a 3-week-old rabbit with a meningoencephalocele is described. The hydrocephalus is caused by obstruction of cerebrospinal fluid circulation in the aqueduct, which is anomalously formed by several minute tubules surrounded by ectopic ependymal cells. The encephalocele is an atrophied part of the right ventricle forced out of the skull by increased CSF pressure. It is suggested that the aqueductal malformation is caused by an ependymal developmental disturbance.