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ME. ST. GEORGE MIYAET ON THE SKELETON OF THE PRIMATES. 
The metacarpus always much exceeds the carpus in length. It does so most, perhaps, 
in the Chimpanzee and Indris, and probably least in the Nycticebinse. 
The proportion of this segment to the spine is greatest in Hylobates, where it 
is sometimes nearly one-fifth, and then in Tarsius, the Chimpanzee, Cheiromys, and 
Ateles. It appears to be least in the Nycticebin®. 
The four outer Metacarpals . — These metacarpals are always more or less enlarged at 
each end. The proximal ends are never much wider transversely than the distal ones, 
and very rarely so at all. It is the case, however, in the Nycticebinge, and at least some- 
times in Lemur, and slightly in Cynocephalus. On the other hand, the distal ends often 
greatly exceed the proximal ends in breadth, as is the case in the Simiin® and Ateles. 
The proximal articular surfaces are more or less concave in Man and Troglodytes. 
In Simia and Hylobates those of the fourth and fifth metacarpals become decidedly 
convex, and in the lower Anthropoidea that of the third becomes convex also, and all 
four become so in the Lemuroidea. 
The proximal surfaces of these metacarpals are in most Primates nearly at right 
angles with the long axes of their shafts; but in Hylobates a line joining these surfaces 
inclines distally as it proceeds ulnad from the index, and this inclination exists slightly 
in Troglodytes, sometimes in Lemur, and a trace of it is to be seen in Man. 
The antero-posterior diameters of the heads (i. e. from dorsum to palm) are never 
greatly in excess of the transverse ones, except in Indris, Lagothrix, and Ateles, though 
slightly so in Simia and Hylobates. Generally the two diameters are about equal. 
The shafts always broaden downwards ( i . e. distad) decidedly. They are always 
flatter on the dorsum than are the metatarsals, and never so laterally compressed. 
Antero-posterior planes extending vertically through the metacarpals from the dorsal, 
to the most prominent parts of the palmar surfaces, have their palmar edges in the 
fourth and fifth metacarpals, inclined towards the middle of the palm. Often the same 
can be said of such a plane traversing metacarpal of the index. 
The shaft of the fifth metacarpal is never much flattened on its palmar surface. 
The palmar surfaces of the metacarpals are more concave disto-proximally than those of 
the metatarsals in the same individual, yet scarcely so, perhaps, in Simia and Hylobates. 
The metacarpals always diverge more or less distally ; least so, perhaps, in Hylobates, 
Simia, and the Nycticebin®, though (except in the last-mentioned subfamily) always 
more so than do their homotypes of the pes. 
The heads are never bent ulnad at their extremities, but continue pretty much in the 
same direction as the shafts. 
The distal articular surfaces are in all formed nearly as in Man, but are shortest 
dorsally in him. 
In Man and the Simiin® they are much larger than the homotypal parts of the pes. 
In the lower forms they are but slightly so. 
First Metacarpal . — This metacarpal attains its greatest absolute length in the Orang. 
As compared with the spine, it is longest in Tarsius, where it is more than one-tenth of 
