ME. ST. GrEOEGE MIVAET ON THE SKELETON OE THE PEIMATES. 
369 
If we extend this definition so as to include those forms and to be applicable at the 
same time to the pes of all Primates except Man, and therefore call every prehensile 
extremity with four or five unguiculate digits, with or without an opposable innermost 
one, “ a hand,” the same term must then be applied to the pes of the Bat and of the 
Parrot ; nor could it be consistently refused even to the extremity of the Sloth ; while 
some Marsupials, and even the Chameleon, might successfully lay claim to the epithet 
“ quadrumanous.” 
M. Isidore Geoffroy St. Hilaire gave a definition of the word in some respects 
better: “ Toute extremite pourvue de doigts allonges prof ondement divises, tres-mobiles 
tres-flexibles et par consequent susceptibles de saisir entre eux et la paume les objets places 
a lew portee ” *. But even this is not exclusively applicable to Apes and Lemuroids, 
especially if the pedal digits of the Gorilla and Siamang are to be spoken of as “ pro - 
f ondement divises .” 
But it is not only on account of form and structure that the same term cannot be 
applied with propriety to the hand of Man and the pes of Apes ; for the careful con- 
sideration of the function of the parts shows more difference between them than is often 
supposed, as well as a greater agreement between the pelvic extremity of Man and that 
of the other genera of the order. All admit that the hand of Man is almost 
exclusively prehensile, his foot almost exclusively locomotive ; and it is commonly 
asserted that in Apes and Lemuroids the pes resembles the hand of Man in function 
far more than it does his foot. I believe, however, that this is not the case ; for, in the 
first place, the foot of Man is not quite destitute of prehensile action, as Ludwig Fick f 
has noticed. In his excellent article on the hand and foot, that author truly observes 
that in locomotion, especially on an uneven surface, there is a certain abduction and 
adduction of the digits in the human foot. Professor Huxley has also called attention 
to its occasional grasping action J. In the second place, though this prehension is 
very much more developed in all the other Primates than in Man, yet in them this pre- 
hension is like that which exists rudimentarily in the human foot and not that of the 
hand of Man. It is a prehension subsidiary to locomotion , and a modification of the action 
of the pes in harmony with the form of the most frequent supporting surfaces (the boughs 
and twigs of trees), not a true assumption of the function of a hand which is still pre- 
served by the anterior extremity. This view, that the prehension of the pes is a loco- 
motive and not a manual prehension, is confirmed by some observations kindly com- 
municated to me by Mr. A. D. Bartlett, Superintendent of the Gardens of the Zoological 
Society, to whom we are indebted for so much interesting information respecting the 
habits of animals. He informs me that he is confident that Apes and Lemurs do not 
use the pes as a hand, that is, for conveying food to the mouth, &c., unless the anterior 
extremities are already occupied; and this is the more remarkable, because he has 
* Archives du Museum d’Histoire Naturelle, 1839, p. 17. 
t “ Hand und Euss,” Muller’s Archiv, 1857, p. 456. 
t Man’s Place in Nature, p. 86. 
