from
The Collaborative International Dictionary of English v.0.48
Syllidian \Syl*lid"i*an\, n. [From NL. Syllis, the typical
genus.] (Zool.)
Any one of numerous species of marine annelids of the family
{Syllidae}.
[1913 Webster]
Note: Many of the species are phosphorescent; others are
remarkable for undergoing strobilation or fission and
for their polymorphism. The egg, in such species,
develops into an asexual individual. When mature, a
number of its posterior segments gradually develop into
one or more sexual individuals which finally break away
and swim free in the sea. The males, females, and
neuters usually differ greatly in form and structure.
[1913 Webster]