II PATTERN OF CONVOLUTIONS 139 



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 Chimpanzee, 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 the brain of a monkey exhibits a sort of 



