CHARACTERISTICS OF THE EXTERNAL EAR 205 



mm. in 29 ears of the negro women, 17.0 in 80 ears of the Filipino 

 men and 16.93 in 14 ears of the Filipino women. 



Index: The index of the concha, as instituted here by me for 

 the first time, is obtained by dividing the length into 100 times 

 the breadth. The index represents the breadth of the concha 

 in terms of the length, the latter always 100. If the index is 

 high, the concha is relatively broad, if the index is low the concha 

 is relatively narrow. The index is 77.21 for the ears of the 

 white men, 82.52 for the ears of the negro men, 80.03 for the ears 

 of the negro women, 69.0 for the ears of the Filipino men and 72.0 

 for the ears of the Filipino women. 



The concha index is more variable among the negroes than 

 among the whites and it is more variable among the negroes 

 than either the physiognomic or morphologic index. The great 

 variations of the concha index need not vitiate its importance, 

 but may add to its significance by indicating the degrees of 

 mixture of negro and white. 



The ears of the negro men with a concha index of 81 and over 

 are more like the ears of the negro, because the average total ear 

 length of the ears in this group is 5.6 mm., and the average 

 age total breadth is 3.7 mm., with a phj^siognomic index of 66.1; 

 whereas the average total ear length of the ears of the negro 

 men with a concha index of 80 and less is 6.1 mm., the average 

 total breadth is 3.8 mm., and the physiognomic index is 62.3, 

 and the ears are therefore like the ears of the white. The con- 

 cha index is thus proven useful as a racial differentiator of a 

 mixed group. 



There is a close correlation between the concha index, the 

 morphologic index, and the physiognomic index. 



Descriptive characters (jjlates 1 to 3) 



True negro ear: In addition to the measurable characters 

 of the negro ear there are descriptive characters which are as 

 distinctive as the measurable ones and they ma}'' enable the 

 observer to obtain a clearer picture of the true negro ear and its 

 parts (12). The ear is small, ahnost flat, close to the head, and 

 the helix is broad as if much folded over. The upper part of 



