Larval nervous systems: true larval and precocious adult

  title={Larval nervous systems: true larval and precocious adult},
  author={Claus Nielsen},
  journal={Journal of Experimental Biology},
  pages={629 - 636}
  • C. Nielsen
  • Published 15 February 2015
  • Biology
  • Journal of Experimental Biology
The apical organ of ciliated larvae of cnidarians and bilaterians is a true larval organ that disappears before or at metamorphosis. It appears to be sensory, probably involved in metamorphosis, but knowledge is scant. The ciliated protostome larvae show ganglia/nerve cords that are retained as the adult central nervous system (CNS). Two structures can be recognized, viz. a pair of cerebral ganglia, which form the major part of the adult brain, and a blastoporal (circumblastoporal) nerve cord… 

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