Volvent is a relatively small nematocyst. They do not have butts, barbs and barbules. Its stem is thick, short, elastic, spineless and closed at the apex. There is only one patch of Sutra inside its capsule. The sutraka remains patchy even when thrown. As soon as it is thrown, it creates many screws like a cork-screw.
Volvent’s work
(i) It grasps the prey.
(ii) It helps in locomotion.