INTERMUSCULAR NERVE CELLS OF EARTHWORM 



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Fig. 1 Tripolar cell in the dorsal portion of a nerve ring at the point of origin 

 of a peripheral nerve. G.7nu., circular muscles; l.mu., longitudinal muscles; n.r., 

 nerve ring; p.n., peripheral nerve; i.e., tripolar cell. Ramon y Cajal method 

 modified. X 540. In all figures the arrow points proximally. 



Fig. 2 A group of spindle-shaped bipolar cells in the intersetal region of a 

 nerve ring, emu., circular muscles; l.mu., longitudinal muscles; n.r., nerve 

 ring; s.b.c, spindle-shaped bipolar cells; vac, vacuole. Ramon y Cajal method 

 modified. X 540. 



Fig. 3 Large spindle-shaped bipolar cell in the ventral portion of a nerve 

 ring, l.mu., longitudinal muscles; n.r., nerve ring; s.b.c, spindle-shaped bipolar 

 cell. Ramon y Cajal method modified. X 540. 



Fig. 4 Small spindle-shaped bipolar cell in the ventral portion of a nerve 

 ring, emu., circular muscles; l.mu., longitudinal muscles; s.b.c, spindle-shaped 

 bipolar cell. Ramon y Cajal method modified. X 540. 



