EXPLANATION OF PLATE XXXIII. 



Cancellaria rodis Whitf. (p. 214). 

 Figs. 1,2. Opposite sides of the oast sliowiiig the featares described. 



Pledrotoma surcultiformis Whitf. (p. 215). 



3. View of a specimea of the ordinary form. 



4. View of a larger and more robust specimen. 



SURCULA perobesa Whitf. (p. 217). 



5, 6. Opposite sides of the best specimens observed. 



Plburotoma regularicostata Whitf. (p. 215). 



7-9. Views of three casts referred to the species. The last, showing no plicae on the last volu- 

 tion, is from the collection Am. Mus. Nat. Hist., New York City. 



Plburotoma (Surcula) altispira Whitf. (p. 216). 



10, 11. Opposite sides of the same cast. Am. Mus. Nat. Hist., New York City. 



12. View of a fragment showing the striae more strongly. 



13. View of another specimen doubtfully of this species. 



Sdrculiies annosus Conrad (p. 218). 



14. View of the back of the specimen upon which Mr. Conrad founded his species and genus. 



SURCULITES CADAVBBOSUS Whitf. (p. 219). 



15, 16, View of the opposite sides of a characteristic form of this species. 

 SURCULITES CURTU8 Whitf. (p. 220). 



17, 18. Two views of an imperfect cast. 



19. View of the larger whorl of a specimen showing the diflference in size of the next one 

 above as compared with that of S. annosa. 



CtPR^A 8ABULOVIRIDIS Whitf. (p. 223). 



20-22. Three views of the same cast, the latter view showing the aperture and its crenulations. 



Calyptraphorus vblatus Conrad (p. 2;;J2). 



23. View of a cast showing the direction and cicatrix of the posterior canal. 

 24, 25. Two views of another cast showing some of the same features and the vertical folds on the 



apical volutions. 

 26, 27. Two views of a specimen from Claiborne, Alabama, for comparison. Collection Am. Mns. 

 Nat. Hist., New York City. 

 364 



