Nemerteans

Movement

Nemerteans generally move slowly, though they have occasionally been documented to successfully prey on spiders or insects. Most nemerteans use their external cilia to glide on surfaces on a trail of slime, some of which is produced by glands in the head. Larger species use muscular waves to crawl, and some aquatic species swim by dorso-ventral undulations. Some species burrow by means of muscular peristalsis, and have powerful muscles. Some species of the suborderMonostilifera, whose proboscis have one active stylet, move by extending the proboscis, sticking it to an object and pulling the animal toward the object.