The reason for the compatibility or otherwise between two bloods was discovered by Landsteiner in I900. He found by a series of cross-testings with red corpuscles and blood sera from different individuals that all bloods could be divided into four chief groups according to the presence or absence from the corpuscles of one or other or both of two agglutinogens A and B. Two corresponding aggluti...

The results of the partial saturation of precipitins with antigens related in derivation to the homologous one give no conclusive evidence of the regular existence in a single immune serum of multiple antibodies which act specifically on various chemical groups of the antigenic proteins. It seems possible to explain at least a part of the facts by the assumption that a single antibody will reac...

1. Methods of preparing a satisfactory antigen having been developed, a technique for performing an agglutination test with B. bacilliformis is made available. 2. As a result of repeated intravenous injection of living cultures of B. bacilliformis at short intervals, rabbits have been found to produce a high titre of specific agglutinins which, under the conditions obtaining in the present seri...

E. P. Pick’ in rgor associated a number of antisubstances individually with the one or the other of the two serum globulin fractions of the Hofmeister classification. In the pseudoglobulin (3.4 to 4.6 saturated ammonium sulphate solution)2 group of antibodies he placed the diphtheria and tetanus antitoxins and the typhoid agglutinin of horse serum; the lower or euglobulin fraction (2 .g to 3.4 ...