176 IMMUNOLOGY 



contained A, the Orangs, both A and B and the Chimpanzees, the 

 A agglutinogen. The serum of the latter also contained agglu- 

 tinins corresponding to those of the human group. 



The biological relationships of the monkeys and apes, corre- 

 lated with the various agglutinogens, are quite well illustrated 

 in Fig. 7 suggested by the illustration used by Landsteiner and 

 Miller (1925). 



Comparison of Agglutinogen in Human and Monkey Blood. — 

 In regard to the agglutinogen found in the red cells of Lemurs 

 and Platyrhinae that is similar to but not identical with the B 

 factor of human cells, Landsteiner and Miller state that the dif- 

 ference is detected when these monkey blood cells are used to 

 absorb the beta agglutinins from type II human serum. They 

 are unable to remove all of the agglutinin although unabsorbed 

 type II serum agglutinates the cells and type III serum does not, 

 or, at most, gives only slight agglutination. 



On the other hand, Landsteiner and Miller* (1925) have shown 

 that the bloods of anthropoid apes "contain groups apparently 

 identical with those of human blood." They were able to assign 

 each blood to one of the four human groups. In regard to the 

 bearing of these results upon the question of the origin of the blood 

 groups in Man, they make the following statement: "If our 

 findings in the anthropoids are taken into consideration, the 

 simplest assumption seems to be Ihat tlie isoagglutinablc factors 

 existed before Man and the anthropoids were differentiated from 

 their common ancestor. If this assumption is not made, one is 

 forced to the conclusion that identical mutations occurred in the 

 evolutionary lines which developed into the Gibbon, Orang, 

 Chimpanzee and Man at some later time." 



Human A and B Factors in Antklropoid Apes. — They also call 

 attention to the interesting distribution of the agglutinogens in 

 the anthropoid apes. Apparently, the Chimpanzee has only the A 

 factor and its blood grouping A and is comparable to that of the 

 American Indian, while the Orangs contain both the A and B 

 factors similar to those of human races other than the Indians. 



Medico-Legal Application of Blood Groups. — A great deal of 

 attention has been given to the mechanism of inheritance of the 

 agglutinogens A and B. Von Dungern and Hirschfeld regarded 



•Landsteiner and Miller; J. Exper. Med. 42: 841, 1925. 



