Brozoans employ ciliated tentacles for feeding. Phylactolaemate lophophores are usually horseshoe-shaped and support up to 100 tentacles. In gymnolaemate species 30 or less tentacles are arranged in a ring. We studied tentacle ultrastructure of 3 freshwater and 9 marine (4 chelostome, 2 ctenostome, 3 cyclostome) species with light and transmission electron microscopy. Tentacles of these species share a common basic design: a hollow tube of basal lamina, covered with epithelium and lined with coelothelium. Tentacles support 5 continuous (frontal, 2 lateral-frontal, 2 lateral) ciliary bands in phylactolaemates and cteno-cheilostomes but 4 in cyclostomes, the latter lacking frontal band. Epithelial cells are arranged in longitudinal rows and their number is inflexible: in all groups there is one abfrontal intermittent row of cells (bearing tufts or single rigid cilia and sending processes into the abfrontal nerve bundle) and also 9 in gymnolaemates, or 11 in phylactolaemates, continuous rows. In all groups, two