AUTHOR'S PREFACE TO SECOND EDITION. 



THE work on the central nervous system, which now for 

 the second time appears before the public, has undergone many 

 changes and been added to in some respects. 



Much that is new has been discovered during the last four 

 years. The author has endeavored to embody the most important 

 of these discoveries in this book. The chapters on histology 

 and histogenesis have been entirely rewritten. At some points 

 nothing new has been added, but the old facts have been 

 presented in a new form (fornix, cornu ammonis, etc.). 



Continued investigations have led the author to modify his 

 views in many respects. In accordance with this, the sections 

 on the oculomotor, the acoustic, and the fibres of the deep 

 marrow have been entirely rewritten. The discoveries which 



/ 



were published shortly before the appearance of this book 

 concerning the course of the tracts in the posterior roots per- 

 mitted us to adopt a much more simple plan of the structure of 

 the spinal cord than was possible in the first edition. 



The wish expressed on many hands that this little work 

 should be adapted to the needs of those who wished to practice 

 under its guidance has been complied with, in that the number 

 of cuts has been increased and the description of individual 

 regions been made more exhaustive. 



A treatise on the comparative anatomy of the nervous 

 system, based on personal investigation, lias been embodied in 

 the work. This addition, which permits us to take a more 

 general morphological view of the macroscopic structures, will 

 also serve as a guide to those who wish to pursue independent 

 courses of study in this most important portion of brain anatomy. 



No comprehensive description of the finer brain-structure 



(v) 



