Plate IV. 



2 . 3> 9. J 4 — l 7 Brissopsis lyrifera. i, 4, 13, 18 Br. elongata. 5, 19 Brissopsis sp. 6 — 8, 10—12 Hemiasier expergitus. 



Fig. 1. Brissopsis elongata, actinal side. r / x . 



— 2. — lyrifera (Mediterranean), abactinal side. T /i- 



— 3. — — — actinal side. I / I . 



— 4. — elongata, abactinal side. '/;. 



— 5. — sp. (« Talisman »), side view. I / I . 



— 6. Hemiastcr expergitus, abactinal side. I / I . 



— 7. — — side view. 3-5/j. 



— 8. — — actinal side. I / I . 



— 9. Brissopsis lyrifera (Mediterranean), side view. I / I . 



— 10. Hcmiaster expergitus, abactinal side. 3-5/j. 



— 11. — — side view. I / I . 



— 12. — — actinal side. 3-5/j. 



— 13. Brissopsis elongata, side view. I / l . 



— 14. — lyrifera (Kattegat), side view. 1 / 1 . 



— 15. — — (Kattegat), abactinal side. 1 / 1 . 



— 16. — — (Mediterranean), side view. 1 / I . 



— 17. — — (Kattegat), actinal side. 1 / l . 



— 18. elongata, subanal fasciole and adjoining parts of the test 2 /,. 



— 19. — sp. («Talisman»), actinal side. l / I . 



