76 H. B. Ferris, M.D. 



averages 6 mm. greater. In the female the head measurements 

 are less than in the Quichua although the head height nearly 

 equals that of the Quichua female. 



The cephalic modulus in the male averages 15.16, with extremes 

 of 15.67 and 14.63, and a range variation of 1.04. In the female 

 the average modulus is 14.75, ^^e extremes 15,13 and 14.47, ^-^d 

 the range of variation .66. The cephalic module is less in the 

 female than in the male and less in both sexes than in the Quichua 

 (15.765, 15.20$) or North American Indians (15.75). 



Head Indices. 



The cephalic index in the male averages 80.38, the extremes are 

 86.67 ^^'^ 73-66, and the variation range 13.01. In the female 

 this index averages 81.36, the extremes are 86.21 and 76.88, and 

 the variation range 9.33. 



The average cephalic index in the male barely places the Machi- 

 ganga in the mesaticephalic group (76-80.9), while the female 

 is brachycephalic (80-). A survey of the seriation tables show 

 that of the males 61.1% are mesaticephalic, 11.1% are dolicho- 

 cephalic, and 27.8% are brachycephalic. In the case of the 

 females 46.7% are mesaticephalic and 53.3% are brachycephalic, 

 none being dolichocephalic. The majority of heads lie near the 

 border line of the mesaticephalic and brachycephalic group, but 

 nearly twice as many females than males are brachycephalic. 



In the male the head height-length index averages 70.93, the 

 extremes are 75.1 and 64.1, and the variation range is ii.o. In 

 the female the average index is 73.84, the extremes are 76.1 and 

 70.4, and the variation range 5.7. In the Machiganga as in the 

 Quichua female the head is relatively high in relation to its 

 length as compared wnth the male and the index is nearly the 

 same in the two groups. The seriation table shows that all of the 

 males and females are hypsicephalic. The Machigangas are even 

 more markedly hypsicephalic than the Quichua. 



The average head height-breadth index in the male is 88.3, 

 in the female 90.8. This is about the same as that of the Quichua 

 and is high as compared with that of most races (75.3 to 97.5 

 Martin). 



The cephalic module-stature index in the male averages 97.3, 

 with extremes of 102. i and 93.9, and a variation range of 8.2. 

 In the female this index averages 102.8, the extremes are 103.6 



