Coeloms, gut, and hydropore formation in C. subdepressus.

A Differentiation of a three-part gut has begun and coelomic sacs (c) were formed next to the archenteron 48 hpf. Detail shows the initial extension of the hydropore channel (arrow) from the left coelom. B Differentiated gut, mouth (m), esophagus (e), and stomach (s), after 3 d. Hidropore channel (arrow) next to the larval epithelium 3 dpf. Scale bars =