- A division of Amphineura where the body is nude or covered with thin spines or setæ, it is without shelly plates.
- A suborder of Amphineura. obtaining the human body vermiform, base missing or merely a groove, and the cuticle pretty much covered with spicules. It provides the people Neomeniidæ and Chætodermatidæ. Identical to Solenogastres. Compare Polyplacophora.
- an order of Amphineura