788 



NORTH AMERICAN INDEX FOSSILS. 



Fig. 1 152. a, Ecphora tampaensis ; b, E. tricostata. (Md. Survey.) 



Family Marginellhle Jousseaume. 



CLXXXIL Marginella Lamarck. 

 Oval or long shells with smooth exterior, low spire and elongate 

 aperture which is slightly canaliculate anteriorly; three to four 

 equal oblique folds on the columella; outer lip often thickened 

 and dentate. Eocenic-Recent. 



587. M. minuta Pfeiffer. (Fig. 11 53, a.) Miocenic-Recent. 

 Spire very low, sunken; last whorl rounded, smooth; aperture 



elongate ; columella with four folds in anterior end ; outer lip thick- 

 ened, smooth. 



Chesapeakean of Maryland and Virginia; Pliocenic of North 

 Carolina and Florida ; Recent on southern Atlantic coast of North 

 America and Cuba. 



588. M. virginiana Conrad. Miocenic-Recent. 

 Larger than the preceding, with the spire low but not sunken; 



body whorl tapering forward, giving the shell a Comis-\ike aspect. 

 Chesapeakean of Virginia; Caloosahatchie beds of Florida; 

 Recent off coast of North America from North Carolina to 

 Yucatan. 



589. M. limatula Conrad. Miocenic-Recent. 

 Small, with low spire and apertural part of last whorl reaching 



up and bending over on the spire ; four plications near the base of 

 columella ; outer lip denticulate within ; aperture widening regu- 

 larly forward. 



