ACTHOR'S ABSTRACT OF THLS PAPER ISSUED 

 BTTHE BIBLIOGRAPHIC SERVICE, JANUART 6 



CONCERNING REISSNER'S FIBER IN TELEOSTS^ 



HOVEY JORDAN 



ONE PLATE (ten FIGURES) AND TWO TEXT FIGURES 



Uncertainty as to the time when I shall be able to resume 

 work on unfinished studies of Reissner's fiber makes it seem best 

 to publish now a short summary of what I have already done and 

 the general conclusions reached, even though the latter may 

 have to be modified as a result of future work. 



According to the original plan, the investigation was to have 

 been conducted along four main lines: first, the histology of 

 the fiber and related structures; secondly, the development of 

 the same; thirdly, the degeneration and regeneration of the 

 fiber following operations; fourthl}^, the function of the fiber. 

 Considerable work has already been done on all of these subjects, 

 but on the last two particularly it is, as yet, incomplete. 



Several different methods of study have been employed, but 

 they need not be described here. It is not necessary, either, to 

 go into any considerable account of the previous work on 

 Reissner's fiber, because an extensive resume will be found in a 

 recent paper by Nicholls.^ 



It may be well, however, to mention the two principal and 

 most recent theories concerning the histological and physiological 

 nature of the fiber. Sargent (1900 to 1904) advocated the view 

 that it is nervous in structure and that functionally it is an 

 'optic-refiex' apparatus extending, in the lumen of the central 

 nervous system, backward from the region of the posterior 

 commissure of the brain to the posterior limit of the spinal cord. 



1 Contributions from the Zoological Laboratory of the Museum of Comparative 

 Zoology at Harvard College, No. 310, and Contributions from the Bermuda 

 Biological Station for Research, No. 100. 



2 NichoUs, G. E. 1917. Some experiments on the nature and function of 

 Reissner's fiber. Jour. Comp. Neur., vol. 27, pp. 117-200, 4 plates, 4 text figures. 



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