ME. ST. G-EOEG-E MIYAET OjST THE SKELETON OE THE PEIMATES. 
345 
Often, in small species especially, there are no distinctly marked fossae, hnt very gene- 
rally there is a depression, on the tibial side towards the summit, which sometimes (as in 
Galago and Perodicticus) extends far down. 
Very generally there is an anterior ridge, and often a posterior or external one 
also. 
Pes. 
The absolute length of this segment is greatest in the Orang and Gorilla, then in Man, 
and afterwards in the Chimpanzee. In Indris and some other lower Simikke it is abso- 
lutely longer than in Hylobates, except the Siamang. 
The proportion borne by the whole length of the pes to that of the spine is far 
greatest in Tarsius, where the first is more than four-fifths of the latter. In Cheiromys, 
Ateles, Simia, and Galago, the length of the pes is more than half that of the spine. 
All the rest exceed the proportion borne by Man (which is about 35‘4 to 100), except 
Lemur and the Nycticebinse. In Cynocephalus, however, the proportion is almost the 
same as in Man. 
The length of the pes, as compared with that of the rest of the pelvic limb, is greatest 
in Simia, Cheiromys, and Tarsius, where the first is decidedly more than half the 
second. In Galago, Hapale, and Nyctipithecus it is about half ; in the rest it is be- 
tween this and two-fifths, except in Hylobates, sometimes in Cynocephalus, and 
in Man. 
The proportion borne by it to the tibia is greatest in Simia, where it is more than 
one-fifth longer than the latter. It approaches this proportion in Cheiromys, and the 
pes is considerably longer than the tibia in Galago and Tarsius also. In all the rest 
the pes is more than four-fifths of the length of that bone, except in Hylobates, the Nyc- 
ticebinse, and Man. 
The length of the pes, compared with that of the manus, is far greatest in Chrysothrix 
and Galago ; the rest are intermediate between the latter genus and Ateles (where the 
proportion is as about 11 3 ’6 to 100), except the Chimpanzee, Cheiromys, and, last and 
least, Hylobates. In these alone, and not always in the Chimpanzee, is the pes 
shorter than the manus. 
Tarsus. 
The absolute length of the tarsus of Man exceeds that of every other Primate, 
though that of the Gorilla approaches his very nearly. 
Its length in proportion to the spine is far greatest in Tarsius, where it almost 
equals two-fifths of the length of the latter. In Galago it is nearly one quarter ; then 
follow Cheiromys, Man, and the Gorilla, where it is more than three-twentieths. The 
rest vary between this and one-twentieth (which Indris, Lemur, and Loris scarcely 
exceed), except Arctocebus. 
The length of the tarsus, as compared with that of the entire pes, is greatest in Galago, 
and then in Man and Tarsius, in all of which the first is between one-half and two-fifths 
