AND AFFINITIES OF THE GORILLA. 281 
of the ‘ hippocampus minor ;’ the beginnings, or incipient homologues, of which cavity 
and part are alone present in the highest Apes. 
Coextensively with this new and improved condition of cerebral growth will be the 
expansion of the cranial cavity, as, with the reduction of the size of the teeth, there 
would be contraction of the jaws; the general result being the change in the propor- 
tions of the face to the cranium, and transmutation of the shape of the head and skuil 
from that shown in vol. iv. pl. 28. to that shown in vol. iv. pl. 30. of the ‘ Transactions 
of the Zoological Society.’ 
In the vertebral column the following changes must take place :—Reduction of the 
length of the cervical spines and, of the ribs of the thirteenth dorsal, converting this 
vertebra, by their anchylosis, into a first lumbar vertebra: liberation of the pleur- 
apophyses of the twenty-third and twenty-fourth vertebre at their distal ends, reduction 
of their thickness, and consequent transformation of the first two sacral into the last 
two lumbar vertebre. The curves and disposition of the different sets or kinds of ‘ true 
vertebra’ must be likewise modified. When the zoologist contrasts Homo with Tro- 
glodytes or Pithecus, by predicating five lumbar vertebrz as peculiar to and characteristic 
of Man, in the limits of such comparison, the tyro is not to suppose that the modified 
homologues of those vertebre are wanting in the Apes; nor will the teacher gain other 
than a passing notoriety by vaunting their presence as a new and valuable discovery, 
with brazen charges of their absolute denial by the real demonstrator of their homo- 
logical existence. 
Finally, in regard to the geographical distribution of the higher Quadrumana, I would 
contrast the peculiarly limited range of the Orangs and Chimpanzees with the cosmo- 
politan character of Mankind. The two species of Orang (Pithecus) are confined to 
Borneo and Sumatra; the two species of Chimpanzee (Troglodytes) are limited to an 
intertropical tract of the western part of Africa. They appear to be inexorably bound 
by climatal influences regulating the assemblage of certain trees and the production of 
certain fruits. With all our care, in regard to choice of food, clothing, and con- 
trivances for artificially maintaining the chief physical conditions of their existence, the 
healthiest specimens of Orang or Chimpanzee, brought over in the vigour of youth, 
perish within a period never exceeding three years, and usually much shorter, in our 
climate. By what metamorphoses, we may ask, has the alleged humanized Chim- 
panzee or Orang been brought to endure all climates? The advocates of ‘‘ transmuta- 
tion” have failed to explain them. Certain it is that those physical differences in 
cerebral, dental, and osteological structure which place, in my estimate of them, the 
genus Homo in a distinct group of the mammalian class, zoologically of higher value 
than the ‘ order,’ are associated with equally contrasted powers of endurance of dif- 
ferent climates, whereby Man has become a denizen of every part of the globe, from the 
torrid to the arctic zones. 
