418 DR MATTHEW YOUNG. 



The table shows that the difference of the two segments of the basi-bregmatic height 

 can by no means have the value attached to it by Klaatsch in his comparison of the 

 Australian and European skulls, and, as the size of the basion and bregmatic angles 

 depends largely on the lengths of these respective segments, the relative size of 

 these angles loses also the significance attributed to it by him. 



This is confirmed by the examination of the measurements of the larger series 

 of 90 Australian skulls. In this group the upper segment of the basi-bregmatic 

 height varies from 51 to 80 mm., with a mean value of 65 '6(5 mm., S.D. 5 '12, 

 V. 779 ; the lower segment ranges in value from 52 to 77 mm., with a mean value 

 of 64*34 mm., which is less than that of the upper segment. The S.D. is 4'94 and 

 the coefficient of variation 7*67, so that the lower segment is slightly less variable 

 than the upper. 



The glabella-bregma chord in the Tasmanian series varies from 94 to 118 mm. 

 and has a mean length of 107*6 mm. ; S.D. is 5*99, V. is 5*56. In Klaatsch's 

 Australian the chord is 106 mm., i.e. within the range of both series, while in the 

 larger Australian series of 90 skulls (unsexed) the chord has a mean value of 

 106*32 mm., with a range of variation from 95 to 121 mm., S.D. 5*41, V. 5*08. In 

 the Scottish series the chord varies in length from 101 to 126 mm., with a mean 

 value 111*62 mm., S.D. 5*509, V. 4*935. The mean length of this chord is thus seen 

 to be decidedly greater in the Scottish series than in the Tasmanian and Australian 

 series. The variability of the line in the Scottish series is decidedly less than in 

 the Tasmanian series, while the chord in the Australian lies between the Scottish 

 and Tasmanian crania. 



The bregma-lambda chord in the Tasmanian series varies from 99 to 127 mm., with 

 a mean value of 115*3 mm. The S.D. is 6*08 and V. is 5*27. In the Scottish series 

 the chord varies in length from 104 to 126 mm., with a mean value of 115 "15 mm. 

 The S.D. is 5*446 and V. is 4*729. 



The mean length of the corresponding chords in the two series is approximately 

 equal, but the variability shown by that in the Tasmanian series is decidedly greater 

 than that in the Scottish series, as in the case of the previous chord. Klaatsch's 

 Australian specimen gives a value of 111 mm., i.e. well within the range of both the 

 Tasmanian and the Scottish series, but Berry's series of dioptrographic tracings of 

 90 Australian skulls shows a range of variation from 100 mm. to 137 mm., and a mean 

 value of 114*18 mm. The S.D. is 6*49 and the coefficient of variation 5*68. 



The lambda-basion chord in the Tasmanian series varies from 103 to 123 mm., 

 with a mean value of 114*3 mm. The S.D. is 4*58 and V. is 4*00. In the Scottish 

 series the chord varies in length from 111 to 135 mm., with a mean value of 

 120*58 mm. The S.D. is 4*675 and V. is 3*87. The mean value of the chord is thus 

 decidedly greater in the latter than in the former, while the variability shown by it 

 is slightly less. In the Australian series of 90 the chord varies in length from 100 to 

 124 mm., with a mean value of 112*01 mm. The standard deviation is 5*31, and the 



