Figure 10

Horizontal electron-microscopic sections of the echinoid axial complex. A-D Psammechinus miliaris (Echinoida) and E, F Echinocardium cordatum (Micrasterina). A Dorsal sac epithelium with myoepithelial cells. B Heavily ciliated canaliculus inside the axial organ. C Axial coelom epithelium with podocyte and haemal lacunae. D Somatocoelomic epithelium. E Axial coelom epithelium with podocyte and haemal lacunae. F Heavily ciliated canaliculus inside the axial organ. ac = axial coelom, aj = adhaerens junctions, bl = basal lamina, cf = collagenous fibers, ci = cilium, cm = circumciliary microvillum, ds = dorsal sac, ec = epithelial cell, hl = haemal lacuna, mf = myofibrils, mv = microvillum, nu = nucleus, pe = pedicel, po = podocyte, so = somatocoel.