138 Proceedings of the Royal Society of Edinburgh. [Sess. 
The Australian and Tasmanian measurements are the original con- 
tributions to the subject of the present work. 
For the European the observations have already been recorded by 
Klaatsch. 
In grouping these several objects of comparison together for purposes 
of calculation, I have regarded the Neanderthal and Spy crania as a 
homogeneous group, and have dealt with the Galley Hill, Brux, and Brtinn 
crania in a like way, and for like reasons. To the former procedure there 
Cro-Magnon. 
European. 
Galley Hiil-Brux-Briinn. 
Tasmanian. 
Australian. 
Spy-Neanderthal. 
Gibraltar. 
Pithecanthropus erectus. 
Anthropoid ape. 
Fig. 2. 
can be no objection, and for the inclusion of the Galley Hill skull with 
those of Brux and Briinn I have been largely influenced by the recently 
expressed opinions of Duckworth (24). 
For the mathematical estimation of the relative evolutionary positions 
of the Tasmanian and the other objects of comparison, I have adopted the 
ingenious methods introduced by Cross. I have not, however, deemed it 
necessary to prolong the calculations beyond what Cross terms the 
“ composite order.” The working of the method is illustrated in Tables 
IV., V., and VI. 
