A. Photograph of a living specimen.

B. Diagram of an adult specimen (Hill, 1972; adapted from Joyeux-Laffuie, 1880). The numbers identify segments 12-17. Segment 12 possesses long aliform notopodia (N). Segment 13 is extremely long and possesses a ciliated cup (CC) on its dorsal surface and a suction disc (not visible) on its ventral surface beneath the ciliated cup. Segments 14, 15, and 16 are modified to form fans used to pump a current of water through the tube. The segments from 17 to the posterior end are genital segments.