Description

In both generations, the transverse ribs of the gill bar meet dorsally, narrowing sharply toward the ventral surface, so that they are far apart from one another ventrally. Solitary zooids: Test soft and smooth. Body elongate and cylindrical. Eight or 9 body muscles that extend rather far ventrally and are usually separated. MI to MIV converging, contiguous, or fused in the mid-dorsal line. A great variation is also found in the number of muscular fibers. Aggregate zooids: Body fusiform because of the presence of short anterior andposterior projections. Five body muscles, all of them meeting in the mid-dorsal region. Embryo between MIV and MV.