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Outlines of zoology . Fig. ii6.—Anteriorpart of nervous sys-tem in Arenicola.—After Vogt and Yung. c, Cerebral part on dorsalsurface: a.r.^ oesoph-ageal ring ; ^., gullet;v.n.c, ventral nerve-cord ; Ln., lateral nerves;oL, otocyst.
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ill.pC Fig. 13. Reconstruction of nervous system. As the plane of the nerve ring is at about 120° to that of the chain system (see Fig. 11), the reconstruction of the
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