390 



Dr. L. S. Beale on the Paths [June 16, 



ganglion, really consists of several fibres coming from different and probably 

 very distant parts. In other vv^ords, I am led to suppose that a single dark- 

 bordered fibre, or rather its axis-cylinder, is the common channel for the 

 passage of many different nerve-currents having different destinations. It is 

 common to a portion of a great many different circuits. The fibres which 

 result from the subdivision of the large fibre vi^hich leaves the cell become 

 exceedingly fine (the j^^^th of an inch in diameter or less), and pursue a 

 very long course before they run parallel with other fibres. As the fibres 

 which have the same destination increase in number, the compound trunk 

 becomes gradually thicker and more distinct. The several individual fibres 

 coalesce and form one trunk, or axis- cylinder, around which the protective 

 white substance of Schwann collects. At the periphery the subdivision of 

 the dark-bordered fibre again occurs, until peripheral fibres as fine as the 

 central component fibres result*. 



Fig. 4. 



Diagram to show the course of the fibres which leave the caudate nerve-cells, a, a 

 are parts of two nerve-cells, and two entire cells are also represented. Fibres 

 from several diflPerent cells unite to form single nerve-fibres, h,h,b. In passing towards 

 the periphery these fibres divide and subdivide ; the resulting subdivisions pass to dif- 

 ferent destinations'. The fine fibres resulting from the subdivision of one of the caudate 

 processes of a nerve-cell may help to form a vast number of dark-bordered nerves, but 

 it is most certain that no single process ever forms one entire axis- cylinder. 



Although it may be premature to devise diagrams of the actual arrange- 

 ment, if I permit myself to attempt this, I shall be able to express the in- 

 ferences to which I have been led up to the present time in a far more 

 intelligible manner than I could by description. But I only offer these 

 schemes as rough suggestions, and feel sure that further observation will 



* " General Observations upon the Peripheral Distribution of Nerves," my 'Archives,' 

 iii. p. 234. " Distribution of Nerves to the Bladder of the Frog," p. 243. " Distribution 

 of Nerves to the Mucous Membrane of the Epiglottis of the Human subject," p. 249. 



