508 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1937 



African type); and a last category containing approximately equal 

 quantities of A and B, comprising Russians, Turks, Arabs, and Jews 

 (intermediate type). This discovery, published in 1919, gave rise to 

 a considerable number of investigations, producing an enormous mass 

 of documents of varying merit, and emphasized the great ethnological 

 interest of blood groups. It would need many pages to give a com- 

 plete account of the results, and we must therefore confine ourselves 

 here to describing a few of the essential features. 



Ilirszfeld thought he could conveniently synthesize these features 

 by calculating for each race a "biochemical index," obtained by 

 dividing the percentage of A by the percentage of B, that is to say, 



A4-AB 

 by establishing the proportionate fraction r>\ at> ' If out of 100 



subjects of a race one found 40 ^, 10 B, and 5 AB, the index would 



40 + 5 45 

 be ..^ , - =Y^=3. The biochemical index for the European typo thus 



fell between 2.5 and 4.5, the index of the Asio-African type between 

 0.5 and 1.1, and the index of the ii\termediate type between 1.3 and 1.8. 



This index has been much used. But the most recent researches 

 have shown, on the one hand that the sero-ethnic types established 

 by Hirszfeld were not exact enough, on the other that the biochemical 

 index was open to serious criticism ; in actual fact, all races in which the 

 proportion of yl is equal to that of B, whatever might be their absolute 

 value, would have a similar index, equal to /, whatever the number of 

 the O's or of the AB's, which is obviously unsatisfactory. 



Many other formulae have been proposed to replace that of Hirsz- 

 feld, but without offering any clear advantages over it. On the other 

 hand successful use has been made of tables, which have proved most 

 instructive. 



The examination of such tables enables us, following Ottenberg, 

 to distinguish a certahi number of quite well marked sero-ethnic types. 

 One such is remarkable for its extreme poverty m both A and B, that is 

 to say it includes ahnost exclusively only the subject of group 0. It 

 comprises the American Indians, the Filipinos, and most of the 

 Eskimos of pure race; it is called the Americo -Pacific type. 



A second type, adjacent, rather deficient in B, but richer in A, is 

 represented by the Australians (Australian type). A third, again poor 

 in B, but very rich in A, includes all western European type. A 

 fourth type is marked by a moderate proportion of A and B, ond 

 includes the Negroes, Melanesians, southern Asiatics (Annamites, 

 Javanese) and is called the Afro-Malay or Afro-south -Asiatic type. 

 A fifth, embracing the Near Easterns (Turks, Persians, Armenians, 

 Arabs) as well as Russians and Czechs, has a moderate proportion of 

 B and a high percentage of A (intermediate tj'pe). A sixth has a very 

 high proportion of A with a considerable but lower proportion of B; 



