PLATE IV. 



Figs. 18, 19. Fhascolion squamatum, Koren and Danielssen. 

 Ficf. 18. The animal magnified 5 times. 

 Fig. 19. Scales from the surface of the body, seen with low power. 



a. A papilla from the proboscis, under liigli power. 



Fig. 20. Phascolion hotulus, u. sp. 

 Fig. 20. Hooked papilla ; magnified 160 times. 



Fig. 21. Phascolion strombi (Montagu). 

 Fig. 21. Specimen from Killibegs Harbour, Ireland ; magnified 4 times. 



Figs. 22, 23. Phascolion Intense, n. sp. 



Fig. 22. The animal magnified thiice. On the proboscis the cutaneous glands are visible. 



Fig. 23. Two adjacent glands with papillae round their openings, from the hind end of 

 the body ; magnified 200 times. 



Figs. 24-27. Aspidosij^hon speculator, n. sp. 

 Fig. 24. The internal structure ; magnified 5 times. 



A. The rough anal shield. 

 a. Anus. 



D. Intestinal spiral. 



H. End of proboscis (not stretched out to its 

 fuU length). 



n. Ventral nerve-cord. 



E. Proboscis. 



Em. Ketractor of the proboscis. 



25'. Segmental organs. 



S. The caudal shield with its radiating grooves. 



Fig. 25. Hooks on the anterior portion of the proboscis ; —^ 



Fig. 26. Hooks from the posterior portion of the proboscis ; '—. 



Fig. 266. Bodies round the opening of the proboscis ; ^. 



Fig. 27. Cutaneous glands, with supporting chitinous plates, viewed from above ; ~^. 



Figs. 28-32. Chcetoderma militare, n. sp. 



Fig. 28. Calcareous spicule, viewed from above and in cross section ; ^^. 



Fig. 29. Calcareous spicules from the median portion of the proboscis, viewed from 

 above and in cross section ; —-. 



Fig. 30. Prickle from the posterior portion of the proboscis and from the body ; 

 magnified 160 times. 



Fig. 31. Prickle of the posterior portion of the body, from the side and in cross section. 

 Fig. 32. The whole animal in its natural size. 



;■. 



Proboscidal portion. | s. Caudal portion. 



