ME. ST. GrEOEGrE MIYAET ON THE SKELETON OE THE PEIMATES. 
325 
and lowest Simiidee ; but even there it is never so large as the corresponding process of 
the pes in the same individual. 
Phalanges. 
In almost all species the metacarpals all support phalanges, the only exceptions 
being in Colobus and Ateles *. 
In all other genera the pollex has two phalanges, and the three outermost digits 
have always three each. The index has also always three phalanges, except in Perodic- 
ticus and Arctocebus, where there are only two. 
The proximal phalanx of the pollex is absolutely longest in Man, the Chimpanzee, 
the Gorilla, and the Orang. 
It is always shorter than the first metacarpal, except in Nyctipithecus, Perodicticus, 
and Cheiromys ; in the last, indeed, it greatly exceeds it. There is very little difference, 
however, in Chrysothrix, Hapale, Lemur, Galago, Loris, and Arctocebus. On the other 
hand, in Colobus it is only one-third of the length of the metacarpal, and in Semno- 
pithecus, Hylobates, and Simia there is also a great difference, though it is always 
more than half the length of the metacarpal. 
The second phalanx is always shorter than the first ; it is less even than half its length 
in Semnopithecus, sometimes in Macacus, in Nyctipithecus, Chrysothrix, Indris, Lemur, 
Galago, and Loris. 
It is always flattened at its distal part from dorsum to palm, except in Hapale, in 
which genus it is laterally compressed, curved and pointed at the end. 
The phalanges of the other digits are of very similar form throughout the order, and, 
as in Man, are convex transversely on the dorsum and flattened on the palmar side of 
each. 
The ultimate phalanges are always flattened from dorsum to palm, except in Hapale, 
where they are laterally compressed, curved and pointed to support the similar-shaped 
claws of that genus. In Cheiromys they are much attenuated. 
The proximal phalanx of the third digit is as long as, or longer than any other 
phalanx of the four outer digits in the Anthropoidea and Tarsius. That of the fourth 
digit is the longest in the Nycticebinse and Cheiromys, but the predominance in length 
of the second phalanx of the fourth digit over the second phalanx of the third digit, 
which occurs in Cheiromys, is quite peculiar to that genus f. 
The relative length of the phalanges may be estimated by selecting those of the third 
digit for comparison. 
Thus the proximal phalanx is always much more than half the length of the third 
* Dr. Lit cae has found one phalanx in the pollex of Colobus, hut none in that of Ateles. . He concludes, 
however, from the form of the distal end of the metacarpal in the latter genus, that a phalanx has existed and 
been lost. Professor Huxley says that there is usually a small and nodular phalanx in Ateles (Medical Times, 
1864, vol. i. p. 93). 
f See Owen, Trans. Zool. Soc. vol. v. pi. 21. fig. 17. 
