230 HEREDITY AND EUGENICS 



Pearl (1908) examined the vital statistics of the city 

 of Buenos Ayres, where Italian, Spanish, and Argentine 

 crosses take place, the last being itself a mixed race. 

 The data extended over a period of ten years, and 

 made possible the comparison of the sex ratio in pure 

 matin2:s with that in crosses. In the former case the 

 ratio was 102-21 : 100, in the latter 105-99: 100, hence 

 a greater excess of male offspring from cross-matings. 

 Little (19 1 9) has made a similar study of the sex 

 ratios from the records of a lying-in hospital in New^ 

 York. These records, unlike the previous ones, in- 

 cluded still-births, and the types of matings included 

 (i) those within each of the following nationalities: 

 English, Irish, Scotch, Italian, Russian, Greek, 

 Austrian, and German; (2) all possible first genera- 

 tion matings between members of these nationalities. 

 The results gave a sex ratio of 106-27 for the pure 

 stocks, and 121-56 for the crosses. This indicates 

 an even more marked increase of male births in the 

 hybrid stocks than the Argentine statistics. Separate 

 examination of the data for still-births indicated 

 that they were more frequent in the pure races than 

 in the crosses. These results indicate that in crosses 

 betw^een European races there is a higher ratio of 

 male births and a lower frequency of still-births, at 

 least in the first generation. The latter is probably 

 a result of hybrid vigour. That crossing a species 

 may alter the sex ratio of the offspring in very 

 marked degree has also been shown in the case of 

 pigeons and other animals. 



Returning to the subject of racial crossing, re- 

 ference may be made to a short study of racial 

 mixture in Hawaii (MacCaughey, 191 9). In these 

 islands intermarriages of Portuguese, Spanish, 

 Haw-aiian, Chinese, Japanese, Americans, English, 

 and other Europeans are taking place. The popula- 

 tion containing this remarkable diversity of races 



