4 
Proceedings of the Royal Society of Edinburgh. [Sess. 
case of hospital data, the sex can be at once distinguished, the determination 
of sex from the skull is not so straightforward a character.” 
Warren (23) refers to the matter in connection with the Naquada race : 
“ The determination of sex has been a matter of very great difficulty, and 
some skeletons were assigned to the sex towards which they possessed a 
preponderance of characters.” 
Lee and Pearson (13) say “ that there is a greater equality of variation 
for the two sexes in uncivilised than in civilised races as regards the organs, 
and the same applies to the skull ” ; and conclude by stating that “ in un- 
civilised races the sexes are more nearly equal in the matter of size varia- 
tion and correlation than in the case of civilised races ” ; and hence these 
authors would also appear to be convinced of this difficulty. 
Klaatsch (17), in referring directly to Australian skulls, says: “ In 
some cases to distinguish sex by the skull is impossible. As regards an 
isolated skull, I should say that in a great majority of cases the specialist 
who has devoted his whole attention to the matter would be able to speak 
with certainty.” 
Aeby, quoted by Havelock Ellis (22), states that there are no sexual 
differences in the skull except size. 
Virchow, also quoted by Ellis, says, “that amongst non-European 
races it is extremely difficult to determine the sex from the skulls, as 
criteria for one race do not hold good for other races, although amongst 
some savage races the differences may be colossal.” 
Bartel (25), in his inaugural dissertation, states that “ owing, therefore, 
to the difficulty in separating collections of skulls into male and female, it 
seems to me that it would always* be wise to work out the constants with 
their probable errors for the skulls as a whole, as well as the constants for 
male and female of any race.” 
I can endorse the opinions expressed by the above authors, for I have 
found the difficulty of determining the sex of the individual Australian 
aboriginal skulls to be a very real one, and consequently I am inclined to 
place more reliance and weight on the results obtained for the crania 
irrespective of their division into sexes. In the present work I have 
separated them, as far as I am able, into male and female. This has been 
done with great care, but is still open to revision. The crania which I 
regarded as doubtful I have placed in that sex to which the majority of 
the determining features pointed. 
One of the greatest problems in all craniological investigations is to 
arrive at the conclusion as to whether the skulls under review are those of 
a pure or homogeneous race , or those of a mixed or heterogeneous race. 
