Our distressing helplessness in curing patients of hydrocephalus has led one of us (Dr. Davidoff) recently to review the treatments attempted for this condition from the days of Hippocrates to the present time.1Of all the remedies so far tried, it appeared to us that the operation reported by Heile2for cases of so-called communicating hydrocephalus is the most promising. This author has now reported a number of cases with very encouraging results. His operation, briefly, consists of unilateral nephrectomy followed by anastomosis of the upper end of the ureter (kidney pelvis) with an opening in the lumbar dura mater. We have had occasion to test this method on one patient, and while the case was, on the whole, an unfavorable one, it served the purpose of demonstrating the mechanical feasibility of the ureterodural anastomosis. REPORT OF A CASE History. —The patient, a child of 21 months, whose