EXPLANATION OK PLATE XXII. 



NaTICA (LUNATIA) IlEMICliYPTA (i:il)l« (p. 118). 



Fig. I. View of a specimen with tbe aperture oblique. 



2, 3. Two views ol'oue haviug the aperture more upright. 



4, 5. 8iuiilar views of one having a slit in the inner lip au<l a miiallcr uuiliilical opening. 

 All (igures somewhat. less than twice natural size. 



N. (LUNATIA) TlIOMKYI Whiff, (p. 120). 



Kii;. H. Back view of a small individual. 



7, S. Two views of a larger specimen, twice natural size. 



N. (Lunatia) iikhos Say {)>. 119). 



FiG.^. 9, 10. Two views, natural size, of the individual used in description. 



ClU'CIBULUM COSTATUM Say (p. 122). 



KiGS. 11, 12. Exterior and interior views of an imperfect specimen, the latter figure showing the inner 

 plate. 



13. Vertical view of a broad, flat specimen. 



14. Lateral viaw of a large crushed specimen. 



Tkochita perarmata Conrad (p. 124). 



Figs. 15, 16. Two views of a gutta-percha cast from a natural mold in the brown clays. 

 17. Lateral view of an exfoliated specimen of the usual size found. 

 18, 19. Other views of a similar form. 



188 



