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HANDBOOK OF PHYSIOLOGY. 



again anastomosing, form plexuses which correspond to each muscle 

 bundle intermediary plexuses. From these plexuses branches consist- 

 ing of primitive fibrils pass in between the individual fibres and anas- 

 tomose. These fibrils either send off finer branches, or terminate them- 

 selves in the nuclei of the muscle cells. 



(2.) In striped muscle the nerves end in motorial end-plates, having 

 first formed, as in the case of unstriped fibres, ground and intermediary 



StPd muscle-fibres of the 



ssus of trog. a, Nerve-end 



6, nerv^. 

 a nucleus in 



plexuses. The fibres are, however, medullated, and when a branch of 

 the intermediary plexus passes to enter a muscle-fibre, its primitive 

 sheath becomes continuous with the sarcolemma, and the axis-cylinder 

 forms a network of its fibrils on the surface of the fibre. This network 

 lies embedded in a flattened granular mass containing nuclei of several 

 kinds; this is the motorial end-plate (figs. 93 and 94). In batrachia, be- 

 sides end-plates, there is another way in which the nerves end in the muscle 

 fibres, viz., by rounded extremities, to which oblong nuclei are attached. 



