ON THE RELATIONS OF MAN WITH THE LOWER ANIMALS 475 
tween the ape and the Marsupial; or, to occupy a lower stand still, to 
those presented by the ape, and, say, the Pachyderm; or, after all, are 
the differences no greater than those which obtain between different 
genera of the Quadrumana? 
These are questions which can plainly enough be settled indepen- 
dently of all theoretical views. Differences of structure can be weighed 
by the mind, as definitely as differences of gravity by the balance ; nor 
can any dialectic skill refine them away. It will save trouble, if the 
attempt be made to answer the last question first—Are the structural 
differences between man and the Quadrumana no greater than those 
between the extreme genera of the Quadrumana? If, as I shall 
endeavour to show, this question can be demonstrably answered in 
the affirmative ;—if it can be proved beyond doubt, that whether we 
consider the skeleton, the muscles, the brain, or the other viscera, man 
is far less distant from Troglodytes or Pithecus, than these apes are 
from the Lemur, and still more from the Galeopithecus or the 
Chetromys, the other queries will need no separate solution. I have 
hardly any new facts to bring forward, nor any need to advance such. 
Thanks to the researches of Duvernoy, Tiedemann, Isidore St. Hilaire, 
Schreeder van der Kolk, Vrolik, Gratiolet, Professor Owen, and others, 
all the elements of the problem have long since been determined. It 
is only necessary to range the admitted facts side by side, in order to 
show that there is no escape from the conclusion. 
And, first, with respect to the differential characters presented by the 
brains of the chimpanzee and orang from that of man on the one hand, 
‘ and those of the lowest quadrumana on the other. I begin with this 
question, because it was my misfortune, at the last meeting of the British 
Association, to find myself compelled to give a diametrical contradiction 
to certain assertions respecting the differences which obtain between the 
brains of the higher apes and of man, which fell from Professor Owen; 
and in the interest of science, it is well that the real or apparent opposi- 
tion of competent inquirers, as to matters of fact, should be put an end 
to as soon as possible, by the refutation of one or the other. Happily, it 
is unnecessary that I should trust to my memory of what took place on 
the occasion to which I refer; for the assertions alluded to were already 
familiar to me, inasmuch as their substance occurs in two of Professor 
Owen’s latest works—the paper “On the Characters, Principles of 
Division, and Primary Groups of the Class Mammalia,’ read before 
the Linnzan Society on February 17th, and April 21st, 1857; and the 
essay “On the Classification of the Mammalia,” delivered as a lecture 
before the University of Cambridge. 
I quote from the former essay, as that intended for an audience 
