TO THE LOWEE ANIMALS. 119 



ape's brain is not likely to give a very valuable opinion 

 respecting the posterior cornu or the hippocampus minor. 

 If a man cannot see a cburcli, it is preposterous to take 

 bis opinion about its altar-piece or painted window — so 

 that I do not feel bound to enter upon any discussion of 

 these points, but content myself with assming the reader 

 that the posterior cornu and the hippocampus minor, have 

 now been seen — ^usually, at least as well developed as in 

 man, and often better — not only in the Chimpanzee, the 

 Orang, and the Gibbon, but in all the genera of the old 

 world baboons and monkeys, and in most of the new world 

 forms, including the Marmosets.* 



In fact, all the abundant and trustworthy evidence 

 (consisting of the results of careful investigations directed 

 to the determination of these very questions, by skilled 

 anatomists) which we now possess, leads to the conviction 

 that, so far from the posterior lobe, the posterior cornu, 

 and the hippocampus minor, being structures peculiar to 

 and characteristic of man, as they have been over and 

 over again 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 

 common to man with the apes. They are among the most 

 distinctly Simian peculiarities which the human organism 

 exhibits. 



As to the convolutions, the brains of the apes exhibit 

 every stage of progress, from the almost smooth brain of 

 the Marmoset, to the Orang and the Chunpanzee, which 

 fall but little below Man. And it is most remarkable 

 that, as soon as all the principal sulci appear, the pattern 

 according to which they are arranged is identical with 

 that of the corresponding sulci of man. The surface of 



* See the note at the end of this essay for a succinct history of the con- 

 troversy to which allusion is here made. 



