28 



Tr ansae tions . — Zoology . 



The male skulls, the female skulls, and the skulls of un- 

 determined sex have all, therefore, average indices in the 

 mesaticephalic group, the females having slightly higher 

 indices than the males. The general average is also low down 

 in the same division. 



The range of variation is ll'l. 



One skull only is brachycephalic. Thirty-one, or 77'5 per 

 cent., are mesaticephalic; eight, or 20 per cent., are dolicho- 

 cephalic ; but no skull has a cephalic index under 70. 



Professor Flower's series of eight has a higher average 

 index — 78 ; but, as already pointed out, his method of calcu- 

 lating the index leads to a higher result than that which I 

 have adopted. My results are more directly comparable with 

 Sir William Turner's. The eight skulls measured by him 

 have an average index of 75-2. The three of the " Novara " 

 collection average 75-9. The Paris skulls average 763 ; and 

 the adults measured by Dr. Barnard Davis, 74-9. 



Combining these results — exclusive of Professor Flower's — 

 with mine, we get from fifty-eight skulls an average cephalic 

 index of 76-1. 



The average glabello-occipital length in my male skulls is 

 187mm. ; in the female, 175"6mm. In the males the maximum 

 transverse diameter of the brain-case averages 142mm.; in 

 the females, 134-2mm. ; while the average of both sexes is 

 140'lmm. 



Vertical Index. 



In all the groups the average index is metriocephalic, close 

 to the lower limit of the group. The index of the female 

 skulls is very slightly higher than in the case of the males, 

 but the small number of female skulls measured makes it 

 impossible to say whether the Morioris are really exceptions 

 to the general rule in this respect. 



The range of variation is 13-3. 



Only two skulls in my set are akrocephalic, and these are 

 both males. Twenty-one, or 51-2 per cent., are metrioce- 

 phalic ; eighteen, or 43-9 per cent., are tapeinocephalic. Five 

 of the females belong to the metriocephalic group ; the others 

 are tapeinocephalic. 



As the mean length-breadth, or cephalic index, is 763, we 

 see that the average Moriori skull is distinctly lower than 



