1. Section on Hematology, Laboratory of Experimental Pathology, National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.
2. Laboratory of Experimental Pathology, National Institute of Arthritis and Metabolic Diseases, Besthesda, Md. Present address: Director of Research, St. Elizabeth's Hospital and Associate Professor of Medicine, Tufts Mediail School, Boston, Mass.