One of the four subkingdoms in the classification of Cuvier. It has been much modified by later writers. [1913 Webster
" It includes those Invertebrata having the body composed of a series of ringlike segments (arthromeres). By some writers, the unsegmented worms (helminths) have also been included; by others it is restricted to the Arthropoda. It corresponds nearly with the Annulosa of some authors. The chief subdivisions are Arthropoda (Insects, Myriapoda, Malacopoda, Arachnida, Pycnogonida, Crustacea); and Anarthropoda, including the Annelida and allied forms."