PREFACE vii 
and Miss N. Karsakoff for their courtesy and 
kindness in granting me permission to copy 
some of their figures; to Mr. Antony Gepp for 
assistance in proof-reading and for the use of two 
photographs; to Mr. George Brebner for kindly 
drawing for this book Figs. 10 and 79, and to 
Mr. G. West for Fig. 87. 
Above all, I am indebted to Miss E. S. Barton 
and Miss A. Lorrain Smith for many drawings 
made specially for this book. 
GEORGE Murray. 
