Pseudoacrorhagi: An endocoelic structure outside the tentacle crown and adorad to the marginal sphincter that contains nematocysts which are the same as those present in the column wall (Stephenson, 1928; p. 18). Pseudoacrorhagi are similar in form to acrorhagi, but the main difference lies in nematocysts; the fact that acrorhagi have holotrichs and pseudoacrorhagi do not contain holotrichs.