Fig. 9 in Morphology of larval and postlarval stages of Priapulopsis bicaudatus (Danielssen, 1869) (Priapulida) from the north atlantic ocean

Fig. 9. Postlarval stages: caudal appendage. A. Many specimens have only one caudal appendage, the bud of the second (arrow) may be visible. B. The anus (an) is located between the two caudal appendages (ca). C. In short caudal appendages, an annulation is indicated. D. In some specimens, the caudal appendage is strongly annulated. E. Arranged in rings, vesicle buds with apical "spinulets" are present. F. The spinules end with one tube. G. In the adult, the stem of the caudal appendage is covered with vesicles. In places where these are broken off, their arrangement in rings becomes evident (arrows). Spinulets are present on the apex of the vesicles (circle). H, I. Magnification of the spinulets (encircled in H). J. In the adult, the apex contains 2–3 tubes. All images SEM, A, E, F from V13482, B, C from V13499, D from V13493, G-J from V13492.