388 



Dr. L. S. Beale on the Paths 



[June 16, 



particular lines ; and it seems to me that the course which the lines take 

 permits of but one explanation of the appearance. Supposing nerve-cur- 

 rents to be passing along the fibres through the substance of the cell. 



Fig. 2. 



A diagram of such a cell as that represented in Plate III. (fig. 1), showing the prin- 

 cipal lines diverging from the fibres at the point where they become continuous with 

 the substance of the cell. These lines may be traced from one fibre across the cell, 

 and may be followed into evert/ other fibre which proceeds from the cell. 



they would follow the exact lines here represented ; and it must be noticed 

 that these lines are more distinct and more numerous in fully-formed than 

 in young cells. They are, I think, lines which result from the frequent 

 passage of nerve-currents in these definite directions. 



Now I have already advanced arguments in favour of the existence of 

 complete nervous circuits, based upon new facts resulting from observations 

 upon a, the peripheral arrangement of the nerves in various tissues* ; b, 

 the course of individual fibres in compound trunks, and the mode of 

 branching and division of nerve-fibres f ; and c, the structure of ganglion- 

 cells |. I venture to consider these lines across the substance of the cau- 

 date nerve-cells as another remarkable fact in favour of the existence of 

 such circuits ; for while the appearance would receive a full and satisfactory 

 explanation upon such an hypothesis, I doubt if it be possible to suggest 

 another explanation which would seem even plausible. 



Nor would it, I think, be possible to adduce any arguments which would 

 so completely upset the view that nerve-force passes centrifugally from one 



* Papers in the PhD. Trans, for 1860 and 1862. Lectures on the Structure ol the 

 Tissues, at the College of Physicians, 1860. 



t " On very fine Nerve-fibres, and on Trunks composed of very fine Fibres alone," Ar- 

 chives of Medicine, vol. iv. p. 19. " On the Branching of Nerve-trunks, and of the sub- 

 division of the individual fibres composing them," Ai'chives, vol. iv. p. 127. 



\ Lectures at the College of Physicians. Papers in Phil. Trans, for 1862 and 1863. 



