8 Preface to the First Edition 



consulting the indices. The books mentioned above are especially good. 

 The histologies by Lewis and Stohr and by Bailey are well suited to begin- 

 ners. Schafer's Microscopic Anatomy (Vol. II, Part I, of Quain's An- 

 atomy), Cunningham's Anatomy, Howell's Physiology, Starling's Physi- 

 ology, and Barker's The Nervous System should be in the reference library 

 available to the student. The yearly Psychological Index and the monthly 

 topical reviews in the Psychological Bulletin are the most efficient guides 

 to recent psychological and psycho-physiological literature. 



For the benefit of those students to whom the technical terms in the text 

 will be new, the proper stress in pronunciation of some of these terms is 

 indicated in the index.* 



I am under obligations to a number of persons who have given me assist- 

 ance in the preparation of this book, especially to Dr. Herbert M. Evans, 

 Dr. Caswell Grave, and Dr. S. O. Mast of the Johns Hopkins University 

 and Dr. Percy W. Cobb of Nela Research Laboratory, who have helped 

 me with suggestions and criticisms, and to Dr. Warner Brown of the Uni- 

 versity of California, Dr. H. M. Johnson of Nela Research Laboratory, 

 and Dr. George R. Wells of Oberlin College, who have done the unpleas- 

 ant work of reading the proof. K. D. 



The Johns Hopkins University, October 15, 1914. 



* In the glossary in the Second Edition. 



