44 EXPRESSION. 
localization of mental functions in different parts 
of the cerebral hemispheres, so fashionable with 
so-called “medical psychologists,’ have no sup- 
port from the facts of comparative anatomy, 
pathology, and experiment, all of which show that 
the hemispheres have a function common to the 
mass of their grey matter, so far as thought is con- 
cerned. Therefore, it would appear that differences 
of shape of head, not involving differences of cranial 
capacity, when they indicate differences of mental 
character, have a purely physiognomic value per- 
fectly similar to that of differences of features of 
the face. We may even go further, and admit 
that it is probable that many of the statements 
of the followers of Gall have a large amount of 
physiognomic truth although their theory is utterly 
wrong. 
These remarks are, I think, sufficient to illustrate 
that in the expressiveness of permanent forms of 
the body a class of phenomena exists, not to be 
explained by reference to the “three principles” 
which appear to Mr. Darwin “to account for most 
of the expressions and gestures involuntarily used 
by man and the lower animals under the influence 
of various emotions and sensations,” viz.: “ Ser- 
viceable associated habits,” “the principle of anti- 
thesis,” and “the principle of actions due to the 
