MODERN EVOLUTION. 



227 



spinal cord into which it is continued, that in reptiles 

 the mass of brain, relatively to the spinal cord, is 

 larger, and still larger in birds, until among the low- 

 est mammals, as the opossums and kangaroos, the 

 brain is so increased in proportion as to be extremely 

 different from that of fish, bird, or reptile. Between 

 these marsupials and the highest or placental mam- 

 mals, there occurs " the greatest leap anywhere made 

 by Nature in her brain work." Then follows this 

 important statement in favour of continuity. 



" As if to demonstrate, by a striking example, the 

 impossibility of erecting any cerebral barrier between 

 man and the apes, Nature has provided us, in the 

 latter animals, with an almost complete series of 

 gradations from brains little higher than that of a 

 Rodent to brains little lower than that of Man." 

 After giving technical descriptions in proof of this, 

 and laying special stress on the presence of the 

 structure known as the " hippocampus minor " in 

 the brain of man as well as of the ape in the de- 

 nial of which Owen cut such a sorry figure, Huxley 

 adds: 



" So far as cerebral structure goes, therefore, it is 

 clear that Man differs less from the Chimpanzee or 

 the Orang than these do even from the Monkeys, 

 and that the difference between the brains of the 

 Chimpanzee and of Man is almost insignificant when 

 compared with that between the Chimpanzee brain 

 and that of a Lemur. . . . Thus, whatever system of 

 organs be studied, the comparison of their modifica- 



