Thenaria (Mesomyaria) whose the column is commonly smooth, rarely tuberculate or with papillae, but without verrucae and other hollow outgrowths. Sphincter mesogloeal. Tentacles sometimes with nematocyst-batteries on their aboral sides, where they are also sometimes thickened; their arrangement regular. Mesenteries not divisible into macro- and microcnemes. Younger mesenteries not bilaterally arranged. Retractors diffuse, rarely circumscribed. No acontia.
Definitions and contained taxa are those of Oscar Carlgren as published in 1949 : Kungl Svenska Vetenskapsakadamiens Handlingar, Series 4, Volume 1, Number 1
Electronic version made possible by NSF grant DEB95-21819 in the PEET program to D. G. Fautin.