Abstract
A series of cases of a syndrome consisting of mental deficiency, a slightly enlarged irregular head, spasticity with wasting and contractures limited to the legs and a curious facies is reported. Frequently associated findings include flexion deformity of the thumbs and a paxodoxical plantar reflex which is flexor in spite of marked spasticity. It is suggested that this syndrome represents a pattern of signs found in conjunction with a variety of aqueductal stenosis related to a mutation on the X chromosome.