PLATE 4. 



Bulbifusus nigeriensis, sp. nov. 



FIG. i. Dorsal view of adult form obscurely showing the sutural platform. 

 FIG. 2. Ventral view of a younger example with an extremely thin labrum, and smooth columella. 



Rostellaria unidigitata, sp. nov. 



FIG. 3. Ventral view of example showing the narrow canal and prominent callosity of the posterior region. 

 FIG. 4. Dorsal aspect of another specimen showing elevated spire and its sculpture, and the wide basal notch. 

 FIG. 5. Ventral view of a younger form with scarcely any sutural platform. 

 FIG. 6. Another young specimen showing posteriorly the callosity and recurved canal, and the sinuous 



margin and reflective lip of the labrum with its digitation. 

 FIG. 7. Young example with a perfect anterior canaliculate prolongation. 



Rostellaria bidigitata, sp. nov. 



FIG. 8. Ventral view showing the earlier plicated whorls, and the double digitation of the labrum. 

 FIG. 9. Another specimen, in profile, showing the marginal details of the labrum and the recurved 

 character of the posterior canal. 



Terebralia, sp. A. 



FIG. 10. An imperfect example showing columella region of fractured aperture, and the rather distant 

 oblique costae. 



Terebralia, sp. B. 



FIG. ii. A probable variety of the same species with numerous and closer costae. 



Sinum africanum, sp. nov. 

 FIG. 12. External view showing small and depressed spiral region and expansive body- whorl, with the 



straight margin to the labrum. 

 FIG. 13. Ventral aspect exhibiting aperture and the strong concentric ridges on the columella side of 



the shell, the dark narrow cavity above represents a fracture. 



Semiterebellum suturocostatum, sp. nov. 



FIG. 14. Apertural view in which the sutural ornamentation is only seen in the earlier volutions. 

 FIG. 15. Profile of another example showing the margined labrum and the recurved posterior canal. 

 FIG. 16. Dorsal aspect of another example showing the backward extent of the posterior canal. 

 FIG. 17. Ventral view of a further specimen showing the posterior callosity of the inner lip. 



Calyptraea crepidularis (Lamarck). 



FIG. 1 8. Spiral aspect of specimen with concentric rows of small spinose tubercles. 

 FIG. 19. Interior of a smaller example showing the perforated and much sunken diaphragm. 



Tugurium nigeriense, sp. nov. 



FIG. 20. Spiral view showing agglutinated surfaces near the suture, and peripheral irregularity. 

 FIG. 21. Apertural view of another specimen with an obscure and partially covered umbilicus. 



Janiopsis nigeriensis, sp. nov. 



FIG. 22. Ventral view of specimen showing a uniplicate columella and an internally ridged labrum. 

 FIG. 23. Dorsal aspect of another example exhibiting the perpendicular plications. 



Hilda turrioulata, sp. nov. 



FIG. 24. Apertural aspect showing columella plications and denticulated labrum. 

 FIG. 25. Dorsal view of another specimen with imperfect basal termination. 



Pteropurpura cf. trioarinata (Lamarck). 

 FIG. 26. Specimen showing the rounded character of the varices, the denticulated labrum, a posterior 



plication on the smooth columella, and the narrowly elongate anterior canal with a short tubular 



accessory extension on the left side. 

 FIG. 27. Dorsal view of same example in which a polyzoan (Membranipora) growth covers a large part of 



the spire. 



