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SMITHSONIAN MISCELLANEOUS COLLECTIONS 



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Prst. 



Br StGne- 



I II \ m IV/ ^ 



VNC B 



PdGngVin 

 Fig. 17. — Nervous system of Annelida. 



A, anterior nervous system of Nereis virens Sars, diagrammatic, showing 

 nerves of cerebral and suboesophageal ganglia (adapted from Hamaker, 1898). 

 B, anterior nervous system of an amphinomid, Hcrmodice carunculata Pallas, 

 showing podial nerves (PdNv) from brain connecting the podial ganglia, and 

 divergence of ventral nerve cords (VNC) through several somites around 

 stomodaeum (from Gustafson, 1930). C, anterior nervous system of Lumbricus 

 terrestris Linn., lateral view, showing retraction of brain into third somite 

 (simplified from Hess, 1925). D, same, dorsal view (from Hess, 1925). 



Br, brain ; Comll, ConiV , commissures of second and fifth somites ; Gngl- 

 GngVI, central ganglion of first to sixth somites; I-VIII, first to eighth somites; 

 Mih, mouth ; PdGng, podial ganglion of second peristomial cirri ; PdGngI, 

 FdGngVIII , podial ganglia of first and eighth somites; PdNv, podial nerve; 

 Perst, peristomium ; Pip, palpus; Prst, prostomium; SoeGng, suboesophageal 

 ganglion; StCoii, stomodaeal nerve connective; StGng, stomodaeal ganglion; 

 Stom, stomodaeum ; Tl, tentacle. 



Nerves of Nereis (fig. A) : a, nerve to stomodaeum; b, tentacle nerve; c, d, 

 nerves to muscles and prostomial integument; e, nerve to proboscis; /, palpus 

 nerve ; g, tegumentary nerve ; h, i, ocular nerves ; /, nerve to nuchal organ ; k, 

 commissural ganglion ; /, m, nerves to proboscis ; n, connective between peri- 

 stomial ganglia; o, nerve to second peristomial ganglion (podial ganglion, 

 PdGng); p, nerve to proboscis; q, r, nerves to muscles and integument of 

 peristomium. 



