PREFACE. V 



ings. The drawings have been so constructed that in the case of 

 a transverse section the reader looks at the caudal surface of the 

 section, the dorsal border is uppermost and the right and left sides 

 correspond to those of the reader. In the case of lateral views 

 and sagittal sections the anterior end is placed at the reader's left. 

 For the sake of the true illustration of the results of other workers 

 and because of the peculiar value of good figures, a large number 

 of illustrations have been copied. The author wishes to express 

 his hearty thanks to the writers who have given permission for 

 the use of their figures. 



At the end of each chapter is a literature list giving the sources 

 for the bulk of the facts contained in the chapter and the author- 

 ities for the facts which support at critical points the general views 

 presented. At the end of each chapter there are given also sug- 

 gestions for laboratory work. These do not constitute a systematic 

 laboratory course, although they offer the material from which 

 each instructor can arrange a course suited to his conditions. The 

 primary intention of these suggestions is to indicate the best or 

 most easily obtainable material for the illustration of the facts 

 in the chapter. It is hoped that in the near future there may be 

 sufficient demand for courses in comparative neurology to warrant 

 the preparation of a systematic laboratory guide. 



The first chapter is intended as a help to prospective investi- 

 gators in the choice of material and methods for their studies. 

 The beginning student may best pass over all but the last two 

 paragraphs of the chapter. 



The author wishes to acknowledge his indebtedness to the larger 

 books on the nervous system of man and mammals, of which those 

 of Barker and Cajal have been the most useful. The most cordial 

 thanks are due to Professor C. Judson Herrick for many helps, 

 including the loan of numerous books and papers and the engrav- 

 ings for Figures 4, 42, 43, 88, 89 and 90, and most of all for reading 

 and criticizing the greater part of the manuscript. 



THE AUTHOR. 



