LITERARY NOTICES. 



Verhandlungen der Anatomischen Gesellschaft auf der Achtzehnten 

 Versammlung in Jena. Anat. Anz. Erganzungsheft zitm 2§ B. 

 1904. 



Schultze, O. Ueber die Entwickelung des peripheren Nervensysteme. 3-7. 

 The growing nerves in the embryo are syncytial in structure. 

 The sheath nuclei are derived from the nuclei of this nervous syncytium. 

 The plexus nervosus profundus of amphibian larvae (Czermak) is a 

 sensory syncytium which is, and has arisen, in continuo with the de- 

 veloping nerve, and is not derived by a fusion of independent units. 

 Schultze's interpretation is in opposition to the neurone theory. 



Koelllker, A. Ueber die Entwickelung der Nervenfasern. 7-13. 



This paper is directly opposed to Schultze's and in favor of the 

 neurone theory. Each axone grows out as a process of a single nerve 

 cell and the sheath nuclei are mesodermal in origin. This mode of 

 development, the author asserts, is followed in Vertebrata, Arthropoda 

 and MoUusca. The process may be simpler in lower forms. 



In the discussion which follows these two papers, Froriep argues 

 for the ectodermal origin of the sheath nuclei by a migration from the 

 central system along the nerve roots. Retzius, Benda, Ballowitz, 

 Harrison and Disse cite various instances and observations in favor 

 of the neurone theory. The necessity of experimental work upon the 

 regeneration of the peripheral end of the severed nerve fiber is empha- 

 sized by Roux and Barfurth. 



Joseph, H. Ueber eigentUmliche Zellstrukturen im Zentralnervensystem von 

 Amphioxus. 16-26. 



The cells in question are the large cells in the anterior region of 

 the nerve cord which v. Kupffer called "dorsale Ganglienplatte." 

 The author finds similar cells in the corresponding position in the 

 caudal region of the cord. All of these dorsal cells, contrary to other 

 authors who differ among themselves, are unipolar, and, in structure, 

 correspond exactly with the "Sehzelle" of Hesse. They are not, how- 

 ever, capped with the pigment cell which is characteristic of the typi- 

 cal "Sehzelle." Their axones pass towards the periphery of the cord 

 and probably enter the posterior roots. In the caudal region of the 

 cord "Sehzelle" occur without the pigment cap, in which case they are 

 identical in structure with the dorsal plate cells of the same region. 



