The Journal of 

 Comparative Neurology and Psychology 



Contents of Volume XV, 1905 



Number 1, January 1905. 



On the Areas of the Axis Cylinder and Medullary Sheath as seen in 

 Cross Sections of the Spinal Nerves of Vertebrates. By Henry 

 H. Donaldson and G. W. Hoke. (From the Neurological 

 Laboratory of the University of Chicago.) With one figure. . . i 



On the Number and Relations of the Ganglion Cells and Medullated 

 Nerve Fibers in the Spinal Nerves of Frogs of Different Ages. 

 By Irving Hardesty. (From the Hearst Anatomical Laboratory 

 of the University of California.) . . . . . . . 17 



Editorial ' 



Psychology and Neurology. ....... 57 



The International Commission on Brain Research. ... 62 



Literary Notices. ........... 65 



Number 2, March, 1905. 



Observations on the Spinal Copd of the Emu and its Segmentation. By 

 Irving Hardesty. {From the Hearst Anatomical Laboratory of the 

 University of California.) With four figures. .... 81 



The Selection of Random Movements as a Factor in Phototaxis. By S. J. 

 Holmes. (From the Zoological Laboratory of the University of Mich- 

 igan.) 98 



Notes on the Development of the Sympathetic Nervous System in the 



Common Toad. By Walter C. Jones, M.D. With twelve figures. 113 



Editorial 



Concerning the Genetic Relations of Types of Action. . . . 132 



The Basis for Taxis and Certain Other Terms in the Behavior of 



Infusoria. ........... 138 



The Problem of Instinct. ........ 144 



A Review of Some Recent Literature on the Chemistry of the Central 

 Nervous System. By Isador H. Coriat. Worcester Insane Hos- 

 pital. . . 148 



Literary Notices 160 



