710 NORTH AMERICAN INDEX FOSSILS. 



348. T. nivea Stimpson. (Fig. 1022, c.) Miocenic ?-Pleistocenic. 

 Long and slender with regular rigid vertical ribs. 



St. Mary's of Maryland, Pliocenic and Pleistocenic of the 

 Carolinas. 



349. T. interrupta (Totten). (Fig. 1022, d.) Miocenic. 

 With narrower intercostal spaces occupied by interrupted spirals ; 



spirals marked on base of body whorl. 



St. Mary's, Choptank, and Calvert formations of Maryland. 



CIII. Chrysallida Carpenter. 

 Like Turbonilla but with both ribs and spirals and columellar 

 tooth. Tertiary. 



350. C. melanoides (Conrad). (Fig. 1022, e.) Miocenic. 

 Small, rather broad ; spirals on side (shoulders) of whorls 



nodulated by ribs ; simple on body of whorl. 

 St. Mary's formation of Maryland. 



CIV. Odostomia Fleming. 

 Like Eulima, but with more depressed sutures and columellar 

 tooth ; surface smooth. Differs from Syrnola in convex whorls 

 and depressed sutures. Tertiary-Recent. 



351. 0. conoidea (Brocchi). (Fig. 1022, /.) Miocenic. 

 Small, short, with elongate body whorl ; angle of young greater 



than of adult. 



Choptank and St. Mary's (?) of Maryland ; Calvert of New 

 Jersey ; Sub-Apennine of Italy. 



Family Scalariid^: Broderip. 

 CV. Scalaria Lam. (Scala Klein.) 

 Turreted non-umbilicated shells, with deep sutures and convex 

 whorls, marked at regular and frequent intervals by smooth varices. 

 Triassic-Recent. 



352. S. sillmani Morton. (Fig. 1023.) " Cretacic. 

 Broad-spired and rather closely coiled, with very oblique sharp 



varices and very fine spirals. Internal mold smooth, with deep 

 sutures. 



Ripleyan of New Jersey and Alabama. 



353. S. sayana Dall. (Fig. 1024, a.) Miocenic. 



