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Nematoda
neap tide tidal period during which the effect of the semidiurnal solar tide opposes the semidiurnal lunar tide. The tidal range is small, the high water being
lower and the low water being higher than normal. Neap tide occurs once
every fortnight.
nektobenthos benthic organisms living close to, but not on or in the sea bottom.
nekton all those pelagic animals that are active swimmers such as most adult
squids, fish, and marine mammals, as opposed to plankton, the passively drifting or weakly swimming organisms.
Nemathelminthes -7Aschelminthes.
nematocyst thread cell, -7Cnidaria.
Nematoda (nematodes, eelworms) phylum of the roundworms, which together
with phyla like Gastrotricha and Rotifera and a few other phyla form the
Aschelminthes. Small, normally microscopic, unsegmented cylindrical worms,
Nematoda.
(Borradaile and Potts 1959)