28 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 93 



The clinical records cannot l)e directly compared with onr tigures ; 

 they lack one of the essentials, which is the proportion in each sex of 

 those with ear tumors to those without ; but as the proportion of the 

 two sexes in the White population at large is much the same, the rela- 

 tive values of the cases reported are probably nearly correct. They 



Relative Frequency of Ear Exostoses in the Two Sexes 



Group 



(in order of frequency 



of exostoses) 



Egyptian 



American : 



Eskimo 



Old Pueblo 



N. Dakota 



Florida 



California 



NE. States 



Peru 



Virginia 



Louisiana 



Arkansas 



S. Dakota, all 



S. Dakota, Mowbridge 

 Kentucky 



Polynesian: 



New Zealand 



Hawaii 



Male to 

 female 

 (male 

 = 100) 



37-2 



72.8 

 87.0 



indicate that for every 100 White males with ear exostoses there are 

 about 27 females with that aiTection. In most of the Indian groups 

 and in both the Polynesian groups the proportion of females was 

 decidedly higher, a fact for which there must be reasons as yet 

 undetermined. 



FREQUENCY OF EXOSTOSES IN THE TWO EARS 



Our material permits us to show definitely the number of individual 

 ears affected in the different groups, and the proportional involve- 

 ment of the two ears in the affected skulls. 



The next table gives for our series of groups the proportions of 

 affected ears in relation to that of the affected skulls or individuals. 

 It will be seen that, barring a few exceptions, in groups where the 

 frequency of individuals or skulls with ear exostoses is smaller, the 

 percentage of single ears free of the growths is larger than in those 

 groups in which the proportion of individuals or skulls affected by 



