perisarc

/per-uh-sahrk/US // ˈpɛr əˌsɑrk //UK // (ˈpɛrɪˌsɑːk) //

周边环境,周边地区,周边,鲈鱼

Definitions

n.名词 noun

1
Zoology.
- : the horny or chitinous outer case or covering protecting the soft parts of hydrozoans.

It flattens itself out into a disc-like form, becomes divided into four lobes, and covered by a cuticle (perisarc).
Over the whole exterior a delicate pellicle—the future perisarc—now becomes secreted.
The stem may contain a single coenosarcal tube (“monosiphonic”) or several united in a common perisarc (“polysiphonic”).
The genera are based upon these differences in the perisarc.