Fig. 13

Schemes of transverse section of tentacles of different types. Blood vessel is not shown. Oral side is to the down; aboral side is at the top. A, B highly specialized tentacles; C – less specialized tentacle; D, E non-specialized tentacles. A Generalized tentacle of lophophorates (based on 32,48,51). B Generalized tentacle of Serpullidae and Sabellidae (based on 85). C Generalized tentacle of Fabriciidae (based on 85) and serpullid Pomatoceros triqueter (based on 73). D Tentacle of Owenia borealis (this study). E Tentacle of holothuria Holothuria forskali (based on 88). Color code: yellow – nerve elemants; blue – coelomic cavity; light brown – myoepithelial cells; dark brown – mucle cells and myoepithelial cells with numerous myofilaments; dark grey – extracellulart matrix; light grey – epithelial cells