15. Umbrella Jndica, 



16. Carinaria vitrea. 



17. Dolabella. 



18. Bullcea. 



19. Bulla aperta. 



20. Infundibulum echinulatum . 



21. Slomatia phjmotis 



22. Stomatella imbricala. 



23. Septaria sen Navicella (Patella Borbonica). 

 a. Back view. 



Under . . 

 <?. Side 



£/. Operculum. 



24. Halyotis vulgaris. 



25. Sigaretus concavus. 



Some of the figures in this Plate are inadvertently reversed. 



