Its profile like a butterfly knot and of which extends anterad,posterad and laterad with one pair of dorsal nerve trunk,ventral nerve trunk and lateral nerve trunk.
Its profile like a butterfly knot and of which extends anterad,posterad and laterad with one pair of dorsal nerve trunk,ventral nerve trunk and lateral nerve trunk.
整个外形像蝴蝶结状，并向体前、后、侧延伸背神经干、腹神经干及侧神经干各对，共对与来自外周神经干联网。