550 THE SYMPATHETIC SYSTEM OF NERVES, BY DR. S. MAYER. 



reserve. He describes in addition connecting fibres proceeding 

 from the nucleolar fibrous plexus to adjoining ganglionic cells, 

 to which he has applied the name of commissural fibres. 

 Arnstein and Kollmann observed fibres which converged from 

 the deeper parts of the cell substance towards the peduncle of 

 the cell, from the plexiform union of which they considered the 

 spiral fibre to arise ; but they were unable to establish the 

 connection of this plexus with the nucleolar filaments. Bidder 

 was unable to satisfy himself of the continuity of the fibrous 

 plexus, the existence of which he allows, with the spiral fibre. 



As regards the physiological significance of these two pro- 

 cesses, we can only form presumptions at present. Arnold 

 regards the straight fibre as the afferent (proceeding from the 

 cerebro-spinal organs) and the spiral as the efferent (running 

 towards the periphery). Arnstein and Kollmann take the 

 same view. According to the researches of Courvoisier, in which 

 he studied the degenerative processes appearing after division 

 of the rami communicantes, the straight fibres first degenerate, 

 then the cells, and lastly the spiral fibres. These results are in 

 favour of Arnold's view. On the other hand, Bidder also, 

 relying upon the results of division of the vagus of the Frog, 

 regards the spiral fibres as the afferent and the straight fibres 

 as the efferent fibres. 



Beale has supplied a large amount of information upon the 

 continuous processes of development and degeneration taking 

 place in growing and adult individuals. His most important 

 arguments rest on the coincident presence in the sympathetic 

 of the same individual, of cells of the most various size, form, 

 number, and nature. Beale admits three types or modes of 

 development of nerve cells. 



In the first of these the cells arise in a finely granular mass 

 resembling that in which the embryonal tissues are developed, 

 with which nerve fibres are in connection ; in the second new 

 cells arise by division of a nerve cell ; and in the third the cells 

 develop from the nuclei of nerve fibres. The observations and 

 deductions of Beale have received little attention in Germany. 

 Sander has opposed the statements of Beale ; though, as far as 

 my experience goes, incorrectly. The various forms of ganglion 

 cells described by Beale, which appear to correspond to various 



