ON THE MAMMALIAN NERVOUS SYSTEM. 



441 



SECTION of Lateral Column on the game Side as the Nerve Stimulated. 



The inference is that the integrity of the lateral column of the same side is 

 connected with 20 per cent, of the cord effect. Additional ground for this conclusion 

 is afforded by the opposite sectional method practised after the manner of MIESCHER 

 and WOROSCHILOFF, which, excluding the lateral column, divides everything else; 

 the knife being placed perpendicularly through the cord from dorsal to ventral surface 

 at the junction of the posterior and lateral columns, and then the cut made obliquely 

 inwards towards the centre, and continued so as to come out on the opposite side. 

 All the structures, with the exception of one lateral column, and the contiguous 

 portion of the lateral horn are thereby severed. In some instances this operation was 

 done piecemeal, first one and then another structure being divided. 



The result of such severance of both posterior and one lateral column is to show 

 that an electrical effect in the cord can still be obtained by stimulating the nerve 

 on the same side as the uninjured lateral column. Its amount, as compared with 

 the total change obtained before the section, is, however, greatly reduced, as is 

 shown in the following Table, comprising experiments made on five Cats. 



* It will be noted that in Cat 19C there ensued an increased effect after the section due to a rise in 

 excitability. 



MDCCCXCI. B. 3 L 



