Figure 9

Budding stage 5 of Hislopia malayensis. Because of their thinness, the peritoneal lining of the digestive tract and the lophophoral base were not reconstructed. (a) View from the frontal side of the bud. The tentacle sheath and vestibular wall are displayed transparently. (b) Similar view as in (a) with the tentacle sheath and vestibular wall omitted and the digestive tract and the epidermal layer of the lophophore displayed transparently. Asterisk marks the border of the still separated fore- and mid-gut. (c) Distal view on the lophophoral base showing the lophophoral coelom with the ganglion situated above it and the mouth opening. The surface of the tentacles has been cut. (d) View of the digestive tract displayed transparently. The shape of the pharynx is better visible than in (b). Asterisk marks the border of the still separated fore- and mid-gut. Abbreviations: a - anus, at - atrium, cae - caecum, es - esophagus, ggl - ganglion, int - intestine, itp - intertentacular pits, lc - lophophoral ring coelom, mo - mouth opening, ph - pharynx, pv - proventiculus, t -tentacles, ts - tentacle sheath, v - vestibulum, vw - vestibular wall. Colors: blue - epidermal layer of the lophophore, crimson - lophophoral ring coelom, green - gut anlage, turquoise - vestibular wall, yellow - nervous system. Scale bar in (a), (b) and (d) = 100 μm, in (c) = 50 μm.