A.-In the presence of premature synostosis of cranial sutures operation is indicated to prevent mental retardation, visual failure, and severe cranial deformity. The weight of the brain is doubled during the first seven months of life, and 80% of its entire growth is completed in the first three years. Any fictor which interferes with this rapid increase of brain volume in early life-and premature synostosis is one such factor-may cause serious disturbance of brain function. In addition in the presence of synostosis evidence of raised intracranial pressure and gross deformity of the head may result. While operation will not be indicated in all cases, there is evidence which strongly suggests that if operation is to be followed by a good result it must be performed in the early months of life before serious symptoms have appeared. Various types of operation have produced satisfactory results. Linear craniectomy is perhaps now the most favoured. Strips of bone are excised along the line of the closed suture or sutures, and the bone margins covered with a thin film of " polytbene." With adequate surgery in skilled hands the risks are extremely small and the results good.