APPENDICULATA, a zoological name introduced by E. Ray Lankester, and employed to denote the large group of animals comprising the Annelida, Arthropoda and Rotifera: all animals composed of a larger or smaller number of hollow rings, each ring possessing typically a pair of hollow lateral appendages, moved by intrinsic muscles and penetrated by blood-spaces. The group is also sometimes called the Annulata, but both terms are now obsolete.