January 17, 1856. 



Professor WILLIAM ALLEN MILLER, M.D., V.P., 



in the Chair. 



The question of Mr. Sievier's readmission into the Society was 

 put to the Ballot, and the Ballot having been taken, Mr. Sievier 

 was declared to he readmitted. 



The following communications were read : 



I. "Anatomical and Physiological Observations on the Organ 

 of Vision, for the purpose of ascertaining the alterations 

 caused by section of the Optic Nerve." By AUGUSTUS 

 WALLER, M.D., F.E.S. Part I. Received January 10, 

 1856. 



(Abstract.) 



The author begins by referring to experimental researches already 

 published by him on the effects produced on the nerves of living 

 animals by section at different points in their course ; and he briefly 

 recapitulates the chief results of these experiments, as follows, viz. 



1. Section of a spinal nerve on the distal side of its ganglion is fol- 

 lowed by degeneration of the part of the nerve beyond the section, 

 whilst the part still connected with the ganglion retains its integrity. 



2. Section of the posterior root of a spinal nerve induces no change 

 in the trunk or branches of the nerve beyond the ganglion, nor in 

 the portion of the root which remains connected with the ganglion, 

 whereas the part of the root attached to the spinal cord, but discon- 

 nected with the ganglion, becomes disorganized. His conclusion 

 from these experiments, which have been varied in different ways, is 

 " that the spinal ganglion is the centre of the nutritive power of the 

 nerve-fibres adherent to it." From other experiments, he concluded 

 that the anterior spinal roots derive their nutritive influence from 

 the spinal cord j and he has little doubt " that every nerve-fibre is in 



