196 PONGO 
length of lower molar series, 72. Ex specimen from Landak, Selenka 
Collection, No. 1, Munich Museum. 
Among the skulls of the Ourang from Landak brought by Mr. 
Selenka, most of which are those of young animals, are two of old 
adult males, and these are entirely different in appearance, quite suffi- 
ciently so, if they belonged to a genus not known to vary so widely 
in cranial characters, to constitute them distinct species. No. 1, whose 
measurements are given above is in some degree the smaller of the 
two, with but a slightly sloping facial region, a braincase considerably 
elevated above the orbits, and with a low bony crest from the posterior 
part of the frontal to the occiput. The rostrum is but moderately 
long, and the orbits are round and not very close together. The face 
is quite broad for its length, and the ridges, rising from the outer side 
of the orbits, form an inverted V on the frontal. The other No. 6, is 
a long, comparatively narrow skull, with a very sloping facial region, 
and a rather long rostrum. ‘The braincase is rounded, rather broad 
across the parietals, and less raised above the orbital ridges than that 
of No. 1, and instead of a crest, the two low ridges, from the outer 7 
side of the orbits, run backward on top of the skull, drawing nearer 
together as they go to the occiput. The orbits are very large, oblong 
in shape, and quite near together. It will thus be seen how absolutely 
different these two skulls are, and yet they do not exhibit any greater 
variation than can easily be found among the crania, not only of all 
forms of Ourangs, but also of the Chimpanzees and Gorillas. 
The following dimensions are from a skull of the Batangtu Dis- 
trict, Borneo: 
Measurements. Adult Male No. 141, from Batangtu Region, 
(Selenka Coll.). Total length, 239; occipito-nasal length, 171; inter- 
temporal width, 74; breadth of braincase, 105; Hensel, 172; zygomatic 
width, 174; extreme width of orbits, 124; width of rostrum at canines, 
73; palatal length, 85.2; length of upper canines, 33; length of upper 
molar series, 61.7; length of mandible, 167; length of lower molar 
series, 70.2. 
This is a large massive skull a little longer than high, with a fairly 
wide braincase but without much depth. There is no long crest, but 
two ridges start from the outer side of the orbits and extend back- 
ward in parallel lines on top of the skull, turning outward at the inter- 
parietal, and join the lateral expansion of the occipital region. The 
orbits are large, higher than wide, separated by a bony septum 
16.9 mm. broad. The rostrum protrudes considerably beyond the line 
