362 ME. ST. GEORGE MI V ART ON THE SKELETON Orf THE PRIMATES. 
the difference is very great, and in this these two extreme forms agree together, and 
differ from all others. 
The production of both, taken together, is greater in Loris than in Man and 
Tarsius, because, though the hallux projects a little less, the pollex projects so much 
more. 
The combined projection is greatest of all in Arctocebus and Perodicticus, from the 
small development of the indices both of the pes and of the manus. 
The hallux, when compared with the longest digit of the pes, is at its maximum in 
Man. Then follow Arctocebus, the Chimpanzee, and Indris, where the proportion is as 
about 7 to 10. In all the rest the proportion is greater than one-half, except in the 
Semnopithecinse and in Simia. 
The length of the hallux, as compared with that of the pollex, is, of course, far greatest 
in Ateles and Colobus, where the first is more than twice and a half the length of the 
second. 
It always considerably exceeds the pollex in length, except in Hylobates, Tarsius, and 
Cheiromys, where it does so but little, and in Hapale and Simia, where it is absolutely 
less, the proportion in the last-named genus being as about 79T to 100. 
The index digit, as compared with the spine, is longest in Simia, where it is nearly 
two-fifths of the length of the latter. It is only slightly less in Ateles, and but little so 
in Cheiromys and Tarsius. In all the rest it is less than in the last, but more than 
one-fifth of the length of the spine, except in Loris, Man, and Lemur, where it is a little 
less, and Perodicticus and Arctocebus, where it is little more than one-tenth. 
The index of the pes is more than twice the length of its homotype in the manus in 
Arctocebus, and in Perodicticus it is more than once and a half as long. 
It is longer than the index of the manus in all except Cheiromys, the Simiinse, and 
Tarsius. 
The longest digit of the pes (whether the third or the fourth), as compared with the 
longest one of the manus, is far greatest in Loris, where the first is nearly once and a half 
of the length of the second ; but in all, except Man, the Simiinae, Ateles, Tarsius, and 
Cheiromys, that of the pes is the longer. Of these last-mentioned genera the proportion 
borne by the digit of the pes is greatest in Ateles and Simia, least in Hylobates, where 
sometimes it is only as about 67*2 to 100. 
Hand and Foot. 
Dr. Lucae, after terminating his description of the variations of structure noticed 
by him in the extremities of the Primates, observes that a more minute examina- 
tion of the pes of apes shows it to agree more with the human hand than with any 
other mammalian extremity, that its resemblances to the human foot are superficial, and 
that the use of the name Quadrumana is thus fully justified. 
His words are, “Denn nicht nur eine genauere anatomische Untersuchung weist 
nach, dass die s. g. ‘ hintere Hand ’ sowohl anatomisch als auch physiologisch weit mehr 
