220 MODE OF TERMINATION OF MOTOR NERVES, BY W. KUHNE. 



precisely similar to those of the frog ; for though the muscular 

 fibres are thicker, the nerve fasciculi are quite as much branched 

 and divided. It is a matter of no difficulty, moreover, to find 

 branches so placed that the point of entrance may be seen in 

 profile ; so that here also, from observations made on the per- 

 fectly fresh and living object, no doubt can exist in regard to 

 the relations that exist between the nerve and muscle. The 

 nerve plates can, on the other hand, be better surveyed and ex- 

 amined in face, enabling the nuclei to be well seen. A structure 

 of beautiful form appears between these in pale bands, consisting 

 of a delicate pattern of parallel lines, which sometimes form 

 longer cords, sometimes sinuous plates, which are again perfo- 

 rated. If the muscle be tetanically contracted, the plates appear 

 folded like the crop of a bird, their softly sinuous edges being 

 angular and serrated. There may also be found at the periphery 

 small delicate processes with club-like ends. Careful focussing 

 with the microscope, with a profile view, shows that the terminal 

 plate lies immediately beneath the membrane of the nerve emi- 

 nence, and just above the granular mass; for it will be found that 

 the greater number of bright nuclei first make their appearance 

 on effecting the adjustment for depth. A few of the latter do, 

 however, lie on the same plane as particular parts of the plate, 

 where, for instance, they, with the granular mass surrounding 

 them, occupy cavities in, or lie between, its folded borders. 

 The above-described image is extraordinarily pale and delicate, 

 and only a practised eye can recognise it in quite fresh and 

 still contracting muscle. It is seen, for example, in the very 

 thin cuticular muscles of the Coluber matrix, which can be 

 placed under the microscope without preparation, and which 

 present a few nerve ends supplying some of the fibres on their 

 surface. Now inasmuch as these muscles contract through 

 their whole extent when their nerves are irritated, and whilst 

 still under observation, we may conclude with certainty that 

 the pale and delicate image of the terminal plate represents 

 truly the living condition, not only of the muscle, but of the 

 nerve, whose termination it forms. 



In those cases where the muscular fibre dies whilst in a state 

 of rest, this image becomes continually clearer and sharper; 

 whilst the contour of the plate, in the first instance, simply 



