ANTHROPOIDEA 705 
The Cebide have a distinct suprascapular notch which is often 
converted by a bar of bone into a foramen; this bar in Mycetes 
giving rise to a peculiar flat process. The acromion and coracoid 
processes are most developed in the Simiide and Ateles. 
The relative length of the fore and hind limbs has been already 
briefly touched upon. The humerus closely resembles that of 
Man throughout the suborder ; the nearest approximation occurring 
in the Simiide. As in the Lemuroidea, this bone never has an 
entepicondylar foramen, but in many of the American forms it has 
a supracondylar perforation. The radius and ulna, like the tibia 
and fibula, are always perfectly distinct throughout their length ; 
and the hand can-be pronated and supinated upon the forearm. 
Man, the Gorilla, and the Chimpanzee differ from other forms in 
having no os centrale in the carpus. 
The brain of Apes is always much smaller in absolute dimensions 
than in Man. Thus, according to Professor Mivart,! “the cranial 
capacity is never less than 55 cubic inches in any normal human 
subject, while in the Orang and Chimpanzee it is but 26 and 27} 
cubic inches respectively. The relative size of the brain varies 
inversely with the size of the whole body, but this is the case in 
warm-blooded vertebrates generally. The extreme length of the 
cerebrum never exceeds, as it does in Man, two and a quarter times 
the length of the basicranial axis. The proportion borne by the 
brain to its nerves is less in the Apes than in Man, as also is that 
borne by the cerebrum to the cerebellum. In general structure 
and form the brain of Apes greatly resembles that of Man. Each 
half of the cerebrum contains a triradiate lateral ventricle, and 
though in some Cercopithecide the posterior. cornu is relatively 
shorter than in man, it again becomes elongated in the Cebide, and 
in many of the latter it is actually longer relatively than it is in 
man. The posterior lobes of the cerebrum are almost always so 
much developed as to cover over the cerebellum, the only exceptions 
being the strangely different forms Mycetes and Hylobates syndactylus. 
In the latter the cerebellum is slightly uncovered, but it is so con- 
siderably in the former. In Chrysothria the posterior lobes are much 
more largely developed relatively than they are in man. The 
cerebrum has almost always a convoluted external surface. In this 
group, however, as in mammals generally, a much-convoluted cere- 
brum is correlated with a considerable absolute bulk of body. Thus 
in Hapale (and there only) we find the cerebrum quite smooth, the 
only groove being that which represents the Sylvian fissure. In 
Simia and Gorilla and Anthropopithecus, on the contrary, it is very 
richly convoluted. A hippocampus minor is present in all Apes, 
and in some of the Cebide it is much larger relatively than it is in 
Man, and is absolutely larger than the hippocampus major. Of all 
1 Article APE, Encyclopedia Britannica, ninth edition. 
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