Xenia is completely soft and doesn't have the ability to "retract" as wood's/glove polyps do(the clavularia have a rigid tube at their bases that they have the ability to retract into). There are actually a few spp of soft corals that are similar that are also commonly reguarded as "xenia"(anthelia, heteroxenia,crespitularia). The hands at the ends of each polyp on the xenia will tend to pulse, grab, or wave.