Ultrastructure of the nuchal organ and cerebral organ in Onchnesoma squamatum (Sipuncula, Phascolionidae)

@article{Purschke1997UltrastructureOT,
  title={Ultrastructure of the nuchal organ and cerebral organ in Onchnesoma squamatum (Sipuncula, Phascolionidae)},
  author={G{\"u}nter Purschke and F. Wolfrath and W. Westheide},
  journal={Zoomorphology},
  year={1997},
  volume={117},
  pages={23-31}
}
Abstract The ultrastructure of the nuchal organ and cerebral organ is described for the first time in a species of the Sipuncula, Onchnesoma squamatum. The nuchal organ is an unpaired structure lying outside and dorsal to the tentacular crown; furrows give the organ a paired appearance. The cerebral organ is an unciliated pad anterior to the nuchal organ. The nuchal organ consists of ciliated supporting cells, non-ciliated supporting cells and bipolar primary sensory cells. The cerebral organ… 

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