472 



MESSRS. F. GOTOH AND V. HORSLEY 



It is evident that the interruption, as far as the posterior column is concerned, is 

 now practically complete for both nerves, hence all the fibres by which these columns 

 are connected with the lumbar nerve roots are now severed, and thus any crossing of 

 nerve impulses out of either posterior column into the lateral columns, or into any 

 structure except the other posterior at a level higher than that of the 12th dorsal, is 

 negatived. 



It remains now to see the influence of section of the lateral column upon the 

 effect. 



E. Influence of Section of the Lateral Columns on the Electrical Effects evoked 



in the Nerve. 



The limitation of the area of stimulation, and the localisation of the descending 

 nerve impulses to the fibres of the excited column, are apparently very complete in the 

 case of the lateral column, so far as the records of muscular movements can show. 

 (Cf. SCHIFF, see p. 347.) 



It remains to be seen to what extent this is true of the particular impulses now 

 studied which, as our previous remarks have shown, must be considered as conveyed 

 into the nerve by the posterior as well as the anterior root fibres. 



For full description of this animal, i.e., appearances during life and death, see <6. 439. 



