170 NATURE OF THE CLOSED NERVE CIRCUITS. 



theory that all nerves pass from living nerve centres 

 as single cords, and terminate or begin in contact with 

 living matter, whether glandular or tissue, including 

 muscular and sense organs. There is, however, also a 

 simplicity in Beale's view, if we represent it thus : 

 Nerve cords are never in continuous contact with any- 

 thing except nerve protoplasm, central or peripheral, 

 and all the work done by the nerve force out of the 

 circuit of the nervous system, is inductive, although 

 that may be employed in two ways, viz., as a physical 

 action in shortening the muscle fibre, or as a stimulus 

 to the living matter of tissues and organs. But the 

 question is not one of simplicity or symmetry, but one 

 of truth and fact. And if Beale's mode is not incom- 

 patible with trophic and secreting nerve influences, we 

 must recollect that Pfliiger's mode is not the only 

 possible mode of communicating nerve influences, so 

 neither can be decided upon by a priori reasoning, 

 but solely by experiment and observation. The ques- 

 tion, as an anatomical one, cannot be said yet to be 

 settled, although I think Dr. Beale has, as yet, success- 

 fully met all the objections to his scheme of nerve 

 distribution.* 



* In spite of Dr. Beale's writings and preparations the termination of 

 nerves in single cords is still generally held by anatomists. One of 

 the latest writers, Dr. Thin (" Journal of Anat. and Physiol.," Nov., 

 1873), describes the tactile corpuscles as representing the termination, 

 each of a single medullated nerve fibre. And, as before said, the ter- 

 mination of single nerve cords in glandular, muscular, and other pro- 

 toplasm is still the prevailing anatomical doctrine. Without question- 

 ing the accuracy of Dr. Beale's anatomy, that in all cases more than 

 one fibre will be found connected with every nerve bioplast, and that 

 loops are the only mode of distributing nerve force to other parts than 

 the nerve bioplasts, central or peripheral, which are in continuous con- 

 tact with the fibre, yet I think he is hardly explicit enough in his 

 theoretical view of the function of the second cord, for he does not 



