1236 



spinal nerve {d) low down to the left. The others are intact sym- 

 pathetic nerves that pass awa}' with the formation of loops and 

 varicosities along the muscle fibres {a and aj) or over and across 

 these {a). I could not show any terminal loops or other connections 

 with the interior of the muscle fibres in this preparation in the case 

 of the nerve fibres (f. The nerve tibres a/, on the other hand, end 

 in a terminal plate with rather abundant ramification. In this, 

 as is shown by the figure, the different nerve fibres come to an end 

 with almost circular terminal loops. At a couple of places in this 

 plate there appeared a connection between the coarser neurofibril 

 net and a peri-terminal network, which of course is in favour of a 

 hjpo-lemmal position for the sympathetic plate. This sympathetic 

 terminal plate (ay) is rather remarkable, its great extension and its 

 abundant neuro-fibrillar ramifications might easily lead one to suppose 

 that we are concerned hei-e with an ordinary motor terminal plate. 

 That this is, however, not the case is shown, first, by the slender 

 non-medullated nerve-fibre, a/, which can be followed in several 

 prepaiations (as the preparation belongs to a continuous series) and 

 secondly by the fact that the nerve is intact after the operation 

 mentioned above and after a long period of degeneration. 



The preparation from which figure 4 is drawn shows, among 

 other things, a muscle fibre with a degenerated motor terminal 

 plate and a short distance (less than the length of the plate in 

 question) from it another terminal plate of a nerve. This last ter- 

 minal plate must consequently be of a sympathetic character to the 

 preceding one. It is certain that the two terminal plates are situated 

 on the same muscle fibre. We see here the interesting fact that 

 two terminal plates of nerves, a motor one and a st/mjyathetic one, 

 the former degenerated and the latter intact, and the sympathetic 

 terminal plate having also a great evteusion on the muscle fibre, 

 are situated on the same muscle fibre and are at a distance from 

 each other such as one finds between the motor terminal plates in 

 a spinal pluri-segmental innervation of the separate muscle fibres ^). 

 In my opinion, however, it is as a rule easy to distinguish, even 

 in preparations where all the nerves are intact, between motor and 

 sympathetic terminal plates of nerves and thus to decide, when 

 several terminal plates of nerves occur on the same muscle fibre, 



*) Erik Agdur: Morphologischer Beweis der doppelten (plurisegmentalen) moto- 

 rischen Innervation der einzelnen quergestreiften Muskelfasern bei den Saugetieren. 

 Anal. Anz. Bd. 49. 1916. 



Erik Agdur: Ueber die piurisegmentellen Innervation der einzelnen querge- 

 streiften Muskelfasern. Anat. Anz. Bd. 50, 1919. 



