70 
THE VOYAGE OF H.M.S. CHALLENGER. 
other craniologists, that the female skull has a less vertical diameter than the male. In 
the male crania the height and breadth in one skull were equal, in all the others 
the height of each skull exceeded its breadth by from 2 to 12 mm. In the female crania 
six were either equal or almost equal in height and breadth, and in only one specimen 
did the height surpass the breadth by 8 mm. The mean gnathic index was 98 '6, i.e., 
mesognathous ; four of the skulls were orthognathous, six mesognathous, and two, both of 
which were females, decidedly prognathous. The mean nasal index was 50, i.e., mesorhine, 
but four specimens were leptorhine, and three were platyrhine. The mean orbital index 
was 87 - 6, i.e., mesoseme ; only two specimens were microseme, whilst five were megaseme. 
The mean palato-maxillary index was 111, and it is remarkable that in two of the 
specimens the length and breadth were equal, whilst in a third the breadth exceeded the 
length by only 2 mm. The mean capacity was 1361 c.c. ; that of four males 1407'5 c.c. ; 
that of seven females 1334 c.c. The general average, as well as that of the males, was meso- 
cephalic, the females microcephalic. The average is much below that of the brachycephali 
measured in Tables IX. and X., which though in part, perhaps, to be accounted for by the 
smaller proportion of male skulls, is presumably also in part due to racial differences. 
This group of Sandwich Islanders was, in its average proportions, dolichocephalic, 
metriocephalic, as a rule phsenozygous, mesognathic, mesorhine, mesoseme, mesuranic, 
and mesocephalic. 
From the great differences in the absolute and relative length and breadth of these 
dolichocephalic crania as compared with the brachycephalic skulls described on p. 65, 
as well as from the difference in their vertical index, I can have no doubt that the 
dolichocephalic skulls belonged to a different race from those that had the brachycephalic 
form and proportions. 
Eleven skulls from Oahu ranged in their cephalic index from 75 to 79 inclusive, and 
were mesaticephalic, therefore, in their proportions. They were all adults ; six were 
presumably males and five females. Although I have grouped them in a table separate 
from the purely brachycephalic and dolichocephalic skulls from the same locality, I do 
not wish it to be supposed that I regard them as belonging to a distinct race. The line, 
indeed, which separates mesaticephalic skulls, on the one hand from dolichocephali, and 
on the other from brachycephali, is quite arbitrary, so that crania with mesaticephalic 
proportions pass almost insensibly either into brachycephalic or dolichocephalic according to 
their place either at the upper or lower term of the series. Such skulls as E, F, N, and 
T (Table XII.), had a cephalic index so little above 74 - 9, which it is customary to assume 
to be the highest term of the dolichocephalic series, and were so closely allied in shape to 
the dolichocephalic skulls (Table XL), that there can, I think, be no doubt they were of 
the same race. If they had therefore been included with them in Table XL, they would 
have slightly raised the cephalic index of the dolichocephalic series. 
