The orders Atremata and Neotremata are frequently grouped together, as the sub-class Inarticulata or Ecardines - the Tretenterata of Davidson - and the orders Protremata and Telotremata, as the Articulata or Testicardines - i the Clistenterata of Davidson.
This primary group was set up to indicate the residuum of Cuvier's Articulata when his class Annelides (the modern Chaetopoda) was removed from that embranchement.
We have, in fact, returned very nearly to Cuvier's conception of a great division or branch, which he called Articulata, including the Arthropoda and the Chaetopoda (Annelides of Lamarck, a name adopted by Cuvier), and differing from it only by the inclusion of the Rotif era.
The name Articulata, introduced by Cuvier, has not been retained by subsequent writers.