Caudina

Stimpson, 1853

10 species

Tentacles 15, with 2 pair digits, distal pair longer than proximal, no terminal unpaired digit. Body stout, tapering posteriorly, usually with distinct caudal portion, which is one third the total length. Radial pieces calcareous ring with conspicuous bifurcate posterior prolongations. Calcareous deposits of various kinds, with no particular kind characteristic of the genus. Phosphatic deposits wanting, occur in one species only. (Deichmann, 1930)

Tentacles with 2 pairs of digits. Caudal appendage long and slender. Retractor muscles absent. Deposits normally tables with spined spires. Cup shaped bodies may often be found among the tables. (Heding, 1931)

Tentacles with 2 pairs of digits, the distal pair longer, but no terminal digit. Body barrel-shaped with a short or long tail. Radial pieces of calcareous ring with short projections. Ossicles large tables, usually with a spire of 4 short pillars, terminating in a few teeth; knobbed buttons or irregular perforated plates also present. (Pawson & Liao, 1992)