BY
G. ELLIOT SMITH, M.A., M.D., F.R.C.P., F.R.S.
Dean of the Faculty of Medicine and Professor of Anatomy
AND
T. H. PEAR, B.Sc.
Lecturer in Experimental Psychology
MANCHESTER
AT THE UNIVERSITY PRESS
12, Lime Grove, Oxford Road
LONGMANS, GREEN & CO.
London, New York, Bombay, Etc.
1917