12 LECTURES ON THE CENTRAL NERVOUS SYSTEM. 



descriptions and drawings as somewhat diagramatic. They 

 only serve the purpose of bringing to your attention, in the most 

 comprehensive manner possible, the most important facts in 

 regard to the course of fibres in the central nervous system. 

 Much is still in dispute, but dimly marked out, with many 

 details wanting. Wherever it was practicable I have given not 

 only those facts which were discovered in a purely anatomical 

 way, but also those tracts which have been determined by well- 

 observed pathological facts. A diagram is not always a picture 

 of the demonstrated course of fibres ; it is often enough only a 

 graphic representation of the conclusions which have been drawn 

 from great numbers of observations. 



A diagram is a changing structure. It must be improved, 

 now here, now there. Certain parts often need to be torn down 

 and rebuilt. It has been contended that we ought not to make 

 use of diagrams in a subject so full of gaps as is our knowledge of 

 the structure of the central nervous system. Let us rather hold, 

 with old Burdach, who wrote in 1819, " The gathering together 

 material for the building is not all that is necessary. Every 

 time that a new supply is obtained, we should renew our 

 attempts to fit it into the building. By thus giving it a form 

 the spirit of investigation is not hampered in its advance ; on 

 the contrary, it is when we first obtain a view of the whole that 

 we see the gaps in our knowledge and learn the direction which 

 our investigations must take in the future. May the attempts 

 at this structure ever be renewed. No one who works at it but 

 adds something to our knowledge." 



[Among recent treatises on the anatomy of the nervous 

 system are the following : 



Kolliker, Handbuch d. mikrosk. Anat. Leipzig, 1854. Meynert, Vom 

 Gehirne der Saugethiere, Strieker's Ilandb. d. Lelire von den Gewehi-n, 1870. 

 Meynert, Psychiatric, I. Wien, 1884. Henle, Handlmch d. Anatomic d. Nerven- 

 systems. Braunschweig, 187 ( J Luys, Recherches sur le Systeme ncrvcux c-cre- 

 brospinal. Paris, 1865 W. Krause, Handbuch d. menschl. Anatonrc, I Bd. 

 Hannover, 1876. Wernicke, Lehrb. d. Gehirnkrankh, I. Cassel, 1881. Schwalbe, 

 Lebrb. d. Neurologic. Brian gen, 18*1. (Contains most of the literature 1111 to 

 1881.). Huguenin, Allg. Pathol. d. Krankh. d. Nervensystems, I. Zurich, 1*73. 

 Kahler, Nervensystem in Tolds. Gewebelehre, 2 Aurl., 1888 Oberstejner, Anlei- 

 tung beim Studium des Baues der nerv. Centralorg. Wien, 1888.- -Mendel, 

 ArtFkel " Gehirn " iu Eulenburg's Realencyklopadie, 2 Aufl. Wieu, 188G.] 



