REPORT ON THE HUMAN CRANIA. 
125 
magnum, I have taken both these dimensions in a large number of the crania. In far 
the greater number the length exceeded the breadth — in the Bush skull Chal. B. by as 
much as 12 mm. — but usually the difference between them was much less, sometimes not 
more than 1 mm. In one New Zealander and in one Chatham Islander these dimensions 
were equal. In one Admiralty Islander the breadth exceeded the length by 1 mm., in 
another by 0*5 mm. 
Variations occurred in the series of skulls in the relative width of the face as 
estimated in the interzygomatic diameter, and that of the cranium in the parietal or 
parieto-squamous region. In the mesaticephalic Bush and Chatham Islanders, the 
brachy cephalic Hawaians and Oahuans, and the dolichocephalic Admiralty Islanders, the 
rule was for the interzygomatic diameter to be less than the interparietal ; in the male 
Australians as a rule the interzygomatic was the greater diameter, but in the Fuegians 
and New Zealanders these relative diameters varied in different crania. In many 
specimens the greater interparietal breadth was associated in the same cranium with a 
relatively large interstephanic breadth, so that the skull was cryptozygous ; but this was 
not constant, so that in some of the crania examined the breadth in the parietal region 
was greater than the interzygomatic diameter, and yet the skulls were phsenozygous. 
The relative length of the frontal, parietal, and occipital arcs varied materially in the 
crania under review. As a rule the occipital longitudinal arc was the smallest of the three, 
but in the Fuegian and so called Patagonian group of skulls the occipital arc was in the 
majority of the specimens longer than either the frontal or parietal. The relative length 
of the frontal and parietal arcs was very inconstant. In the whole series of crania, except 
the New Guinea, the Loyalty and Admiralty Islanders and New Hebrideans, the tendency 
was for the frontal arc to exceed the parietal, but in the Melanesians it was the rule for 
the parietal arc to be longer than the frontal, and in the Loyalty Islanders very consider- 
ably to exceed it, so that this may be considered as a racial character of the Papuans. 
In a paper on Cranial Deformities, published twenty years ago, in which I discussed the 
mode of production of the scaphocephalic skull 1 I stated that one cranial bone might 
infringe upon the areas of adjacent bones if its ossification proceeded at a more rapid 
rate than theirs. This will doubtless account for the variations in the relative magnitude 
of the cranial bones, more especially those of the vault of the skull, in different individuals. 
For the fibrous primordial matrix in which these bones arise is continuous over the cranial 
vault, and does not have the limits of the several bones defined in it by sharp lines of 
demarcation. The ossific spicules, growing at a greater rate from a centre within one 
area than in the others surrounding it, would necessarily extend the area of the bone to 
which they belong and give it a greater superficial magnitude. It is probable that in 
those Melanesian crania in which the parietal longitudinal arc dominates so much over the 
frontal and occipital, that the parietal ossific centres are relatively more active than both 
1 Natural History Review, January 1864, 
