EUGENICS RECORD OFFICE. 



151 



part of the male offspring are normal. If the excess of hemophilic and 

 of color-blind males is due to sex-linked lethal factors, families in which 

 all the males are hemophilic or color-blind should include among them a 

 considerable number in which this condition is due to linkage of the sex- 

 linked lethal wdth the normal allelomorphs of hemophilia and of color- 

 blindness. This should be accompanied by a relative excess of females 

 in which no sex-linked lethals are present. Table 17 shows the totals 

 for the four categories of famihes in question: 



In both cases, although the data are gathered from very different 

 sources, there is a significantly lower sex-ratio in the matings where 

 it is to be expected. 



We may, therefore, conclude that statistical analysis of human pedi- 

 grees of hemophilia and color-blindness indicate strongly that sex- 

 linked lethal factors are present in man. Only detailed long-time in- 

 vestigations covering several generations of unusually prolific famihes 

 can furnish additional proof. 



HEREDITY OF HAIR, EYE, AND SKIN COLOR, AND HAIR FORM. 



The Director has spent some time in securing additional and im- 

 proved data on the family recurrence of peculiarities in pigmentation 

 and hair form. Acknowledgment is made of the courtesies of the 

 superintendent and principals of the Huntington schools and of the 

 principals and instructors in biology at Girls' High School and Erasmus 

 Hall, Brooklyn, and Evander Childs High School, the Bronx, for co- 

 operation in this study. 



MUSICAL FAMILIES. 



Some months ago Professor C. E. Seashore, of the State University 

 of Iowa, invented a method of expressing quantitatively variations in 

 sense of pitch, intensity, time consonance, and tonal memory. Tests 

 of these capacities were made by the use of phonograph records pre- 

 pared in his laboratorj^ After conferences with Professor Seashore 

 in 1919, it was decided to ask the Institution for an appropriation to 

 enable his student. Miss Hazel M. Stanton, to make tests on musical 

 families in New York, Boston, and vicinity, and this was granted. She 



