PLATE III. 



Ilionia GrALTENSis (page 14). 



Figure 1. Left valve of a specimen from Durham. 

 " la. Right " " " " " " 

 " 16. Side view of a right valve, from Gait. 



SuBTJLiTES COMPACTUS (page 15). 



Figure 2. Side view, somewhat enlarged. This figure is not quite accurate, 

 and another has accordingly been given on Plate 7. 



CODONOOHEILTJS STRIATUM (page lY). 



Figure 3. Side view of the most perfect specimen known, about twice the 

 natural size. 



HoLOPEA Geacia, Billings (page 18). 

 Figure 4. Side view of the type of the species. 



Ctclonema sulcatum, Hall (page 18). 

 Figure 5. Specimen with most of the test preserved. 



EuOMPHALUS MACROLINEATUS, Whitfield (page 20). 

 Figure 6- Side view of a specimen from Durham. 



Figure 7. 



Teochonema inoenatum (page 19). 

 The most perfect specimen known to the writer. 



Steapaeollus ceenulatus (page 21). 



Figure 8. Large specimen from Durham, as seen from above. 

 " 8a. Side view of a smaller individual from Durham. 

 " 8&. Basal aspect of the same. 



BUOMPHALUS GrALTENSis (page 21). 



Figure 9. A nearly perfect cast, as seen from above. 

 " 9a. Lateral aspect of the same specimen. 



Opeecula of GtASteeopoda (page .33). 



Figure 10. View of operculum No. 1., as seen from above. 

 " lOo. Side view of the same specimen. 

 " 106. Basal aspect of do. 



" 11. Base of operculum No. 2. A side view of this specimen is given 

 on plate 7. 



Pleueotomaeia otclostoma (page 23). 



Figure 12. Side view of a specimen from Durham. 

 " 12a. Another view of the same specimen, to show the circular aperture. 



