1913-14.] Curvatures of the Tasmanian Aboriginal Cranium. 133 
(18), but they have been incorporated in the present work for necessary 
reasons. For further explanation of the observations of the median 
sagittal curvatures in Table I., the reader is referred to fig. 1, where the 
method of determining the various measurements is displayed. 
As regards the degree of flattening or otherwise of the Tasmanian 
aboriginal crania, it is very important to notice that Duckworth (24), in 
his recently published (1912) Prehistoric Man, says, “The flatness of a 
cranial arc is but one of many characters awaiting research,” and adds, 
Br 
“ More research is needed.” In the same work, he also states that “ Dr 
Sera (25) has been led to pay particular attention to the remarkably 
flattened cranial vaulting ” of certain crania previously mentioned in 
Duckworth’s work. He also adds that, “as a rule, this flattening has been 
regarded as representative of a stage in the evolution of a highly developed 
type of human skull from a more lowly, in fact a Simian one. This 
conclusion is challenged by Dr Sera. The position adopted is that a 
flattened skull need not in every case owe its presence to such a condition 
as an early stage of evolution assigns to it. Environment, for which we 
may here read climatic conditions, is a possible and alternative influence. 
If sufficient evidence can be adduced to show that the flattened cranial 
