SCIENCE 



Friday, March 19, 1915 



CONTENTS 



The American Association for the Advance- 

 ment of Science: — 



The Classification of Nervous Beactions : 

 Professor Theodore Hough 407 



The Dedication of the New Building of the 

 Mellon Institute: W. A. Hamor 418 



Charles Edtvin Bessey 420 



Scientific Notes and News 421 



University and Educational Neivs 4^3 



Discussion and Correspondence: — 



The Fundamental Equation of Mechanics: 

 Wm. Kent. A Course in Agriculture for 

 Non-technical Colleges: Dr. Frederick H. 

 Blodgett 424 



Scientific BooTcs: — 



Miinsterherg's Psychology, General and Ap- 

 plied: Professor Howard C. Warren. 

 Soiart on Design of Polyphase Generators 

 and Motors; Blondel on Synchronous Motors 

 and Converters ; Morse on Storage Batteries: 

 Professor Ealph E. Lawrence 428 



Special Articles: — 



Correlation between Egg-laying Activity 

 and Yellow Pigment in the Domestic Fowl: 

 Dr. a. F. Blakeslee and D. E. Warner. 432 



The American Society of Zoologists: Pro- 

 fessor Caswell Grave 434 



MSS. intended for publication and books, etc., intended for 

 reTiew should bo sent to Professor J. McKeeu Cattell, Garrison- 

 gn-Hudson, N. Y. 



TSE CLASSIFICATION OF NERVOUS BE- 

 ACTIONSt 



It is within the memory of most of us 

 what a distinct advance was made in the 

 definiteness of our thinking about nervous 

 reactions when the introduction and im- 

 provement of the Golgi method led up to 

 the conception of the neurone doctrine. 

 Previous to that time our mental picture 

 of the reflex mechanism was not essen- 

 tially incorrect; but its conception of the 

 nature of the connection between the sen- 

 sory fiber and the motor nerve cell was 

 indefinite. When the new histological 

 method revealed the posterior root fibers 

 entering the cord and by means of collat- 

 erals ending in the immediate neighbor- 

 hood of motor cells, there was revealed an 

 almost diagrammatic mechanism which ex- 

 plained many reflex phenomena; and we 

 can recall the enthusiasm with which all 

 proceeded to construct combinations of 

 neurones to serve as the anatomical basis 

 of the various known functions of the nerv- 

 ous system; indeed, we have been engaged 

 in this fascinating pastime ever since. 



This is exactly as it should be, for only 

 in this way could the possibilities of the 

 new discovery be tried out. There is 

 danger, however, in anything which is at- 

 tractively definite; sometimes because it 

 may belong among those things which are 

 "too good to be true" ; but more frequently 

 because its successful explanation of many 

 of the phenomena with which it deals may 

 blind us to its failure to explain others; 



1 Address of the chairman and vice-president 

 of Section K (Physiology and Experimental Med- 

 icine), American Association for the Advance- 

 ment of Science, Philadelphia, December 31, 1914. 



