A Transitional Form between Man and the Apes. 13 
ealvaria of Trinil with the crania of Neanderthal and Spy. Indeed the 
agreement with these is great, as I already stated in my first description. I then 
avoided closer comparison, because they had been held by Virchow and others 
to be pathological. But recently I have been in Liége, and there have studied, 
during nearly a whole morning, together with Professor Fraipont, his famous 
Spy-skulls, one of which is exactly like the Neanderthal skull, comparing them 
directly with the Java calvaria. I am now wholly convinced that they are 
not at all pathological, and was much struck by the great resemblance with the 
cranium of Pithecanthropus. Both Professor Fraipont and I could find no other 
decisive differentiating features except the size, the flattening of the parietal region 
in the Java calvaria, and the relatively much greater dimensions of its orbital part. 
Also the same two more important last-mentioned differences I find only between 
it and the very interesting atavistic microcephalic skull described by Professor 
Cunningham. ‘These characters of the Java calvaria I believe it would be 
impossible ever to find in human crania. No microcephalic skull, so far as I 
know, shows them. It may be that the Trinil skull is in other respects to be 
compared with the Neanderthal and Spy skulls, as also with microcephalic skulls, 
yet it is different from these, also through its lesser size. For the Neanderthal skull, 
Huxley estimated the capacity at 1230 ¢.cm.; others, with more right in my 
opinion, estimated these at 300 c.cm. higher; in any case the linear dimensions of 
the Neanderthal skull are greater than those of the fossil skull, and the same holds 
for the Spy skull; their length and breadth are about 15 mm. more. 
On closer comparison with a distinct genus of Anthropoid Ape we find—as I 
stated before, and as many naturalists, who saw the skull-cap or even my figures, 
grant—the next analogous is Hylobates. From this genus I really can only find 
two important differences, viz. in the size and in the downward slope of the 
occiput. The “orbital part of the skull”—as it was recently termed by Virchow— 
is quite different from this part in Man. I have good reason to suppose that not 
unimportant pieces of this part have been lost; but still it is not difficult to see, on 
the right side of the fossil calvaria, that it is not at all like that in Man. The 
proportion between the lengths of the orbital and cerebral parts of the skull-cap 
is exactly the same as in the skulls of the Gibbons. I therein quite agree with 
Virchow. Only the dimensions of the fossil skull are about twice as large as those 
of the largest Gibbon skull. In Hylobates only do we find sometimes the supra- 
inial arch of the cranium as high as in the Pithecanthropus. 
I will now go a little closer into a very important character, by which the Java 
cranium, notwithstanding its resemblance to the Ape, especially Hylobates, is 
more decidedly related to human structure. I mean the strong slope forward of 
the infra-inial part of the occiput. It was, without doubt—as Sir William 
Turner, when speaking of my description, also admits—in relation with the 
