﻿133 Florida Oligocene Shells 15 



Cornell collections of Tertiary fossils have been made. 



Olivella diadematophoros, n. s. 

 PI. IV, fig. -i. 

 Shell small, rather tumid, four-whorled ; suture deeply 

 channelled ; surface smooth except for a diadem-like coronation. 

 Outer lip simple, thin, pillar with two strong folds. Length of 

 shell 3 ; greatest width 1.5 mm. 

 Oak Grove, Florida. 

 Mr. Aldrich's collection. 



Marginella chipolana, n. s. 

 PI. IV, fig. 2. 



Shell small, biconic, broad in proportion to its length, 

 smooth and polished, four-whorled ; spire acute ; suture distinct; 

 aperture rather broad, two-thirds the length of the shell ; outer 

 lip thickened, marginated externally, with about ten denticles 

 extending along the inner margin from the anterior to the pos- 

 terior canals, the posterior denticles being the most prominent 

 and widely separated while the anterior are small and crowded ; 

 inner lip with four sub-equal plaits, the anterior being somewhat 

 more oblique and pronounced. 



Length of shell 6 ; greatest width 4 mm. 



Oligocene of the Chipola marls, Bailey's Ferry, Florida. 



Cornell University collection. 



Marginella Cornelliana, n. s. 

 PI. IV, fig. 3. 

 Shell of moderate size, biconic, very smooth and highly 

 polished, four-whorled, the convexities of the whorls of the spire 

 not wholly concealed by the callus glaze ; aperture fully two- 

 thirds the length of the shell, rather narrow ; outer lip thickened 

 and reflexed, marginated sharply externally, bearing six nearly 

 obsolete denticles, visible only with a lens ; inner lip with a 

 slight callus and four strong plaits, the anterior very oblique, the 

 posterior nearly horizontal. 



