14 Dusois—On Pithecanthropus erectus : 
curve of the encephalon, and the greater relative volume of the cerebrum, which 
are associated with the erect attitude. It is much stronger than in the Anthropoid 
Apes, and differs only a little from human proportions. 
In fig. 2 I have drawn the opisthion (7.e. the median point of the hinder border 
of the foramen magnum) of the fossil cranium on the ground of comparative 
measurements of the cranium No. 2 of Spy, and of many Hylobates’ skulls, 
which also in the form of the related region approach nearest the Trinil 
cranium. The curves are then placed on one line, in equal length for all drawn 
from the opisthion to the glabella. The inclination of the nuchal part of the 
a 
<A apua 
Spy IT 
= 
po 
* 
sees: 
So zenees 
sseee 
w 
S 
Fic. 2.—Profile outlines of the skulls of Pithecanthropus erectus (Pe), a Papua man, the Spy man No. 1, 
the microcephal Joe described by Professor Cunningham, and of Hylobates leuciscus (H1), 
Semnopithecus maurus (Sm), and Anthropopithecus troglodytes (At). Gl—Glabella. Op—Opisthion. 
Jn—Linea nuche superior. Lni—Linea nuche inferior. 
occiput is much nearer to modern Man than to the Anthropoids ; for other human 
skulls, which I measured for this purpose, are in proportion almost exactly the 
same as the Papua skull, which is drawn here. The Spy cranium and that of the 
microcephal Joe, described by Professor Cunningham, approach very much that 
of the Pithecanthropus. 
In the Chimpanzee, the Gorilla, the Orang-utan, and the different species of 
Hylobates, I find that the angle which the median line of the nuchal plane makes 
with the median line from the glabella to the hinder bord of the foramen magnum 
only varies between 94° and 97°. In the lower Apes I find it in Semnopithecus 
