178 BKAIN-WEIGHT AND SIZE IJST RELATION" 



man from, the stolid, and the civilised man from the savage. A care- 

 ful study of the subject, however, shows some remarkable deviations 

 from such a scale of progression. In this Mr. Darwin would recog- 

 nize an analogy to greatly more ample proofs of inequality between 

 the organic source of power and the manifestations of mental energy; 

 as, for example, in the ant, with its cerebral ganglia not so large as 

 the quarter of a small pin's head, displaying instincts and apparent 

 affections of wonderful intensity and compass. Viewed in this aspect, 

 "the brain of an ant is one of the most marvellous atoms of matter 

 in the world, perhaps more marvellous than the brain of man." Here^ 

 however, we look on elements of contrast rather than analogy ; and 

 seek in vain in this direction for any appreciable test of the sound- 

 ness of the popular belief in the size of the brain as a measure of 

 intellectual power. It is otherwise when we turn to the anthropo- 

 morpha. There, alike in the scientific and in the popular creed, very 

 special and exceptional affinities to man are admitted; and the more 

 careful study of their anatomical structure tends to increase the 

 recognized points of analogy. 



Mr. Lockhart Clarke, in a contribution to Dr. Maudsley's work on 

 the Physiology and Pathology of Mind, gives a minute description of 

 the concentric layers of nervous substance which combine to form the 

 convolutions of the human brain, and of the forms and disposition 

 of the various nerve-cells of which its vesicular structure consists. 

 Comparing the human brain with those of other animals, he says : 

 " Between the cells of the convolutions in man and those of the ape 

 tribe I could not perceive any difference whatever ; but they cer- 

 tainly differ in some respects from those of the larger mammalia — 

 from those, for instance, of the ox, sheep, or cat."* Apart from the 

 difference in volume (55 to 115 cub. in.), the only distinctive features, 

 according- to Professor Huxley, between the brain of the anthropo- 

 morpha and that of man, are " the filling up of the occipito-temporal 

 fissure ; the greater complexity and less symmetry of the other sulci 

 and gyri; the less excavation of the orbital face of the frontal lobe ; 

 and the larger size of the cerebral hemispheres, as compared with the 

 cerebellum and the cerebral nerves." 



The brain of the orang is the one which seems most nearly to 

 approximate to that of man. In volume it is about twenty-six or 

 twenty-seven cubic inches; or about half the minimum size of a 



* " Insanity and its Treatment," by G. P. Blandford, M.D., p. 10., 



