THE VOYAGE OF H.M.S. CHALLENGER. 
and curved line; a more vertical forehead, a greater flattening of the vertex and 
consequently a diminished height of the skull, with frequently, though not invariably, a 
greater breadth of the cranium in the region of the parietal eminences than near the 
squamous suture, have been regarded as characteristic of female skulls. 1 
A careful enquiry into these different characters will, without much difficulty, enable 
the craniologist to pronounce definitely as to the sex of a large proportion of the human 
crania which may be submitted to him for examination. But in large collections 
of skulls there are always specimens the characters of which are not sufficiently 
pronounced to enable one to state with certainty to which sex they had belonged. 
Various specimens of this kind have been distinguished in the tables which accompany 
this memoir by a query. 
In determining several of the indices I have in many instances been saved the 
labour of calculation by employing the very useful tables which Professor Flower has 
appended to his catalogue of the human crania in the Museum of the Eoyal College of 
Surgeons of England. 2 
The determination of the internal or cubic capacity of the cranial cavity, so as to ensure 
accuracy and uniformity in result is admittedly one of the most difficult measurements to 
be undertaken by the craniographer. The amount of shot, or sand, or glass beads, or seeds of 
different kinds which a skull can contain varies, as has been pointed out, especially by M. 
Broca, 3 Dr. Wyman, 4 M. Topinard, 5 and Dr. E. Schmidt/ with the size of the particles, with 
the dimensions of the funnel through which they are poured into the cranial cavity, with 
the rapidity of their flow, and with the extent to which the skull is shaken and the particles 
made to subside and be compacted together. In a similar manner, the estimation of the 
amount of the material poured into a skull varies with the height of the cubic measure, 
with the rate at which the substance is poured into the measure, and with the amount 
of succussion to which it is subjected. M. Broca strove to give uniformity to the guaging 
and cubage of a skull by always employing shot of a definite size (No. 8), by pouring it 
through a funnel, the neck of which had a narrow diameter, and by ramming the shot 
when in the skull so as to ensure the closest possible approximation of the particles. The 
shot was then emptied from the skull into measures of a definite height, with the aid of a 
funnel having a neck of a particular diameter. 
1 M. Broca's Instructions Craniologiques, already cited, and Prof. Ecker's article in Archiv fiir Anthropologic, 
Bd. i. p. 83, may be consulted with great advantage on the sexual characters of crania. 
2 Professor Welcker has also given in the Archiv fiir Anthropologic, Bd. iii. Heft 3, excellent tables for the deter- 
mination of the indices of breadth and height. 
3 Mem. de la Soc. oV Anthropologic de Paris, ser. 2, t. i. p. 63, 1872, also t. ii. p. 1 ; and Instructions Craniologiques. 
4 Observations on Crania, Proc. Boston Soc. Nat. Hist, vol. xi., April, 1868. 
5 Anthropology, English translation, p. 226, and more fully in Revue d' 'Anthropologic, t. v. p. 385, 1882. I wish to 
express my obligations to M. Paul Topinard for the interesting demonstration which he gave me of the mode of 
using M. Broca's method for obtaining the cubic capacity and the precautions which it is necessary to employ in order 
to avoid error. 
6 Archiv fiir Anthropologic, Bd. xiii. p. 53, 1882. 
