Synonyms

Circumoral nerve ring : The nerve ring in adult Echinoderms, where there is no convincing evidence that the nervous system (Monro, 1783), which is a nerve net, is divided into central nervous system (Meckel, 1817) and peripheral nervous system (Meckel, 1817); see Bullock & Horridge (1965, p. 1525), Cobb (1995, p. 411). There is also a circumoral nerve ring with a ganglion (Galen, c173) in Phoronida; see Bullock & Horridge (1965, p. 641).