1. Senior Instructor in Pharmacology and Senior Research Instructor in Anesthesiology.
2. Professor of Anesthesiology and Assistant Professor of Pharmacology, University of Rochester School of Medicine and Dentistry, Rochester, New York. Received from the University of Rochester School of Medicine and Dentistry, Department of Pharmacology and Division of Anesthesiology, Department of Surgery; accepted for publication April 8, 1965. A preliminary report has been presented at the Fall M