W. R. Macdonell 
99 
(G) Photographic Studi/ of the Moorfields Skulls*. 
A photographic study of the Moorfields crania brings out even more markedly 
than the numerical measurements the wide divergence of the English skull of the 
Londoner of two centuries ago, and possibly of his successor of to-day, from 
the types of our nearest continental neighbours. A magnificent cranium like that 
on Plate XVII. is exceptional, although it also shows the very prevalent bathro- 
cephaly; crania like those on Plates XIII. to XVI. are far more fi'equent, and one 
recognises at once features of a somewhat primitive or debased type. It seems 
urgently necessary that a large series of crania from another part of the kingdom, and 
if possible from a rural district, and of about the same period, should be examined. 
Is it possible that the contents of plague pits in a city like London only provide us 
with a debased sample of the population ? Or again, is the Londoner of to-day 
really different from tliis man of two centuries ago ? If he be, is the change the 
result of selection, immigration, or altered environment ? One must confess to 
a certain feeling of imrest, so long as the two largest series of English skulls, of 
which we have complete measurements, namely the Whitechapel and Moorfields 
series, give the English these not very flattering cranial characters. 
The remainder of our photograjjhs have been selected to preserve records of 
special abnormalities for future comparison and reference. Plate IX. gives a fine 
example of an ossicle of the bregma ; Plate VI, completes our English series of 
tripartite interparietals, the ossa triangularia being detached and the os pentagonale 
fused; compare Biometrika, Vol. ill. p. 220 and Plates XXXVI.— XXXIX. ; Plates 
VII. and VIII. illustrate double and triple ossicles of the lambda and should be 
compared with Plate XXXIV. of the Whitechapel memoir; Plate X. provides a 
striking instance of supernumerary condyle with articulating facet ; Plate XII. 
shows the post-coronal depression frequently referred to, and is besides an 
illustration of the very common receding forehead; and Plate XL reproduces a 
remarkably symmetrical pear-shaped norma verticalis. Such pear-shaped domes— 
often curiously regular and smooth in texture — will be familiar to all craniologists 
as occurring in a small percentage of cases in most cranial series. An index 
to this characteristic might possibly be taken as follows : The skull being 
adjusted to the horizontal plane on the craniophor, mark on the sagittal circum- 
ference the points in which the vertical planes through the greatest breadth (B) 
and through the minimum forehead breadth (B') meet this circumference; let the 
horizontal distance between these points be Df. Then 100 {B — B')jD is the 
suggested index. It might perhaps be termed the Pyroid Index. I suggest that 
the Pyroid Index will be found to be of some racial and sexual value, and I hope 
that a study of it at least in English crania will soon be published. 
* I have to thank Professor Karl Pearson very cordially for the great trouble he has taken in 
photographing the skulls. 
t Easily measured with the spanner described in Biometrika, Vol. i. p. 415. 
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