ABSTRACT
G. Leboucq points out that although the difference between the cortical development of the ape and of the monkey is not very great, the coefficients for the different Primates roughly correspond to prevalent ideas on the relative intelligence of the animals. Regardless of any possible correlation between this coefficient and intelligence, and allowing for experimental errors, the values of R, like the other figures which he has provided, once again seem to indicate constancy in the construction of the brain of the Old World Primates. The brains of the Primates—including, as Elliot Smith has shown, those of the Lemuroidea—are constructed on the same basal plan. Anatomists have been at pains to emphasize the proportional similarities between the brains of different Primates. The chapter focuses on certain morphological points which seem to bear on the strange conclusion, suggested by experiments on behaviour, that monkeys and apes may be more or less equal in “intelligence.”
