Brain of Man 163 



and in the size of some parts compared with others. 

 Next, he showed that, so far from its being possible to 

 erect anj^ barrier in the structure of the brain between 

 man and the apes, there exists among the mammals an 

 almost complete series of gradations from brains a little 

 higher than that of the rabbit to brains a little lower 

 than that of man. He laid great stress on 



"the remarkable circumstance that though, so far as our 

 present knowledge extends, there is one structural break in the 

 series of forms of simian brains, this hiatus does not lie between 

 man and the man-like apes, but between the lower and the 

 lowest simians ; or, in other words, between the old- and new- 

 world apes and monkeys, and the lemurs. Every lemur which 

 has yet been examined, in fact, has its cerebellum partially 

 visible from above, and its posterior lobe, with the contained 

 posterior cornu and hippocampus minor, more or less rudi- 

 mentary. Every marmoset, American monkey, old-world 

 monkey, baboon, or man-like ape, on the contrary, has its 

 cerebellum entirely hidden, posteriorly, by the cerebral lobes, 

 and possesses a large posterior cornu, with a well-developed 

 hippocampus minor." . . . " So far from the posterior lobe, 

 the posterior cornu, and the hippocampus minor being struct- 

 ures peculiar to, and characteristic of man, as they have over 

 and over again been asserted to be, even after the publication 

 of the clearest demonstration of the reverse, it is precisely these 

 structures which are the most marked cerebral characters com- 

 mon to man with the apes. They are among the most distinctly 

 simiaupeculiarities which the human organism exhibits," . . . 

 "Man differs from the chimpanzee or the orang, so far as 

 cerebral structure goes, less than these do from the monkeys, 

 and the difference between the brains of the chimpanzee and 

 of man is almost insignificant, when compared with that be- 

 tween the chimpanzee brain and that of a lemur." 



Although Huxley found no structural differences be- 

 tween the brains of man and of anthropoid apes, he was 

 careful to lay great stress on the important difference 



