1864.] 



of Nerve- currents in Nerve- cells. 



389 



cell, as from a centre, towards its peripheral destination, as this fact. So 

 far from the fibres radiating from one cell, or from the nucleus as some 

 suppose, in different directions, all the fibres which reach the cell are com- 

 plex, and contain lines which pass uninterruptedly through it into other 

 fibres. Instead of the cell being the point from which nerve-currents 

 radiate in different directions along single fibres, it is the common point 

 where a number of circuits having the most different distribution intersect, 

 cross, or decussate. The so-called cell is a part of a circuit, or rather of 

 a great number of different circuits. 



Diagi'am to show the possible relation to one another of various circuits traversing 

 a single caudate nerve- cell, a may be a circuit connecting a peripheral sensitive sur- 

 face with the cell ; h may be the path of a motor impulse ; c and d other circuits 

 passing to other cells or other peripheral parts. A current passing along the fibre a 

 might induce cm'rents in the three other fibres, h, c, d, which traverse the same cell. 



I conclude that at first the formed material of the cell is quite soft and 

 almost homogeneous, but that as currents traverse it in certain definite 

 lines, difference in texture and composition is produced in these lines, and 

 perhaps after a time they become more or less separated from one another, 

 and insulated by the intervening material. 



It may perhaps be carrying speculation upon the meaning of minute 

 anatomical facts too far to suggest that a nerve-current traversing one of 

 these numerous paths or channels through the cell may influence all the 

 lines running more or less parallel to it (fig. 3) . 



I have ascertained that fibres emanating from different caudate nerve- 

 cells situated at a distance from one another (fig. 4, a, a) at length meet 

 and run on together as a compound fibre {b, b, b), so that I am compelled 

 to conclude (and the inference is in harmony with facts derived from ob- 

 servations of a different kind) that every single nerve-fibre entering into the 

 formation of the trunk of a spinal nerve, or single fibre passing from a 



Fig;. 3. 



a 



d 



2f 2 



