In repeating the work of Ashby1 while studying the length of life of red blood corpuscles by the transfusion and agglutination method, it was found that in many patients more than 1 per cent, of their red cells could not be agglutinated by serums, even before transfusion. The cells which did not agglutinate were found to consist of reticulocytes, normoblasts and cells with various types of "inclusion granules." The nature of these cells and their behavior under various conditions was studied in fifteen patients with various types of anemias in the wards of the Peter Bent Brigham Hospital, ten dogs and 130 normal persons.
The method of Ashby is based on the fact that the cells of Type II patients who have been transfused with Type IV (Moss) blood can be subsequently separated by agglutination with Type IV serum, which leaves the Type IV cells free. Under such conditions normal,