Fig. 9.

Details of the digestive tract of Cinctipora elegans. Semithin sections, toluidine blue. a Longitudinal section showing all major parts of the digestive tract. The mouth opening proceeds via the pharynx and esophagus towards the caecum. From the latter the gut continues with the ciliated pylorus before entering the intestine which terminates with the anus within the tentacle sheath. b Cross-section of the foregut (pharynx-esophagus) which consists of vacuolated cells. Note the lumen is filled with secretory vesicles (asterisks) as observed at the lophophoral base and the frontal side of the tentacles. c Longitudinal section of the pylorus showing several apical parts of the gut epithelium being shed into the gut lumen. d Cross-section of the pharynx showing the triradial arrangement of the lumen. Abbreviations: a – anus, cae – caecum, cw – cystid skeletal wall, ep – esophagus, ex – exosaccal cavity, fg – foregut, int – intestine, mo – mouth opening, ms – membranous sac, p – interzooidal communication pore, pc – pseudocoelomocytes, ph – pharynx, py – pylorus, t – tentacles