544 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXI. 



On combining' thet*e data on cranial capacit}' in full-grown orangs it 

 i.s found that the measurement ranges in the males from 355 (Delisle) 

 to 540 (Abbott) and even 575 (Bischott), and in the females from 300 

 (Selenka) to 490 (Selenka), which is a great variation. The greatest 

 and smallest capacities in the Abbott series are not attended with any 

 other structural peculiarities which would point to animals belonging 

 to distinct species, and must be ascri))ed solely to individual diversit3\ 

 LINEAR DIMENSIONS AND FORM OF THE SKULL. 



Measurements of the cranial vault in orangs and pai'ticularly in the 

 males otier difficulties which are not encountered in man. The region 

 above the nasal bone, corresponding in part to the human glabella, 

 varies much even in the same sex and is not suitable for the anterior 

 starting point of the long diameter of the vault. The point chosen 

 instead was the intersection of the median line with a horizontal 

 line obtained b}^ passing the rod of the sliding compass down the 

 frontal bone until it rested on the orbital arches. This point marks 

 ver}^ nearly the anterior boundary of the vault, and corresponds closeh' 

 to Broca's ophryon as well as to the point from winch S-hwalbe, 

 Selenka, and Kohlt>rugge measured. The length was measured from 

 that ad md.rliinim^ which generally corresponds to some point on the 

 vertical occipital ridge. The breadth was the greatest diameter at the 

 height of the temporo-parietal sutures, the temporal bone lielow 

 expatiding in thickness and rendering all measurements over it imprac- 

 ticable. Selenka" measured the breadth in nuich the same maimer. 

 The height taken was the standard one, basion to bregma (or where 

 crest existed to its base over bregma). The following table gives the 

 results of these measurements: 



Cranial raeai^urements. 



Male orangs. 



Cat. No. 



142183 . 

 14219.5 . 



142188 . 

 142200 . 



142197 . 



142180 . 



142181 . 

 142196 . 



142198 . 

 142194 . 

 142192 . 



142199 . 



142189 . 



Length. Breadth, 



Cm. 

 11.8 

 13.0 

 12.3 



{•'■) 

 12.1 



(?) 

 11.9 

 12.1 

 12.6 

 12.3 

 12.7 

 12.1 

 12.4 



Cm. 



10.2 



11.2 



10.2 



10.0 



10.3 



10.0 



9.4 



9.7 



10.0 



9.7 



10.0 



9.8 



9.4 



Length- 

 breadth 

 Index 

 (length = 

 100). 



Average. 12. .5 



R*i"^e { 11;8 



10.0 

 9.4 

 1L2 



80.0 

 75.8 

 86.4 



Height. 



Cm. 



9.3 



bll.5 



11.1 



9.4 



(■•') 



(?) 



9.5 



(?) 



10.3 



9.5 



'' 10. 



''9.6 



''9.2 



9.9 

 9.2 

 11.5 



Female orangs. 



Cat. No. Length. 



142201 

 142202 

 142193 

 142170 

 142169 

 142185 

 142187 

 142182 

 142190 

 142186 

 142191 



Cm. 

 12.0 

 11.3 

 11.2 

 11.2 

 11.3 

 11.5 

 11.2 

 11.5 

 11.2 

 11.7 

 11.8 



11.4 

 11.2 

 12.0 



Breadth. 



Length- 

 breadth 



index Height, 

 (length = 



100). 



Cm. 



9.8 

 9.2 

 9.2 

 9.2 

 9.3 

 8.9 

 9.1 

 9.8 

 9.2 

 9.6 

 9.5 



9.3 



81.7 

 81.4 

 82.1 

 82.1 

 82.3 

 77.4 

 81.2 

 85. 2 

 82.1 

 82.0 

 80.5 



81.7 

 77.4 

 85.2 



Cm. 



9.2 

 (?) 

 9.1 

 9.3 

 9.2 

 9.4 

 8.8 

 8.9 

 9.0 

 8.6 

 8.7 



9.0 

 8.6 

 9.4 



b Approximately. 



'■'Studien ueber Entwickelung-sgesehichte der Tiere, 1898, pp. 22, 23. 



