﻿NEW CRETACEOUS AND EOCENE FOSSILS. 295 



MENESTHO, Midler. 



Menestho striata, (Pasithea striata, Lea.) This shell does not represent the genus 

 Monoptygma, Lea, the type of which is an Ancilla with a tumid columella. 

 Menestho and Monoptygma are very different genera, but are associated in "Adams' 

 Genera." 



CERITHIODERMA, Conrad. 



Acutely ovate, striate ; labium grooved and umbilicate ; columella recurved in- 

 teriorly or subtruncate ; aperture patulous, margin obtusely rounded inferiorly ; 

 beak very short, narrow, recurved. 



Cerithioderma prima. PI. 47, fig. 30. Acutely ovate; spire conical; whirls 

 rounded, eight ; body whirl large and ventricose ; whirls of spire reticulated ; body 

 whirl with longitudinal ribs or undulations and very fine lines ; revolving lines pro- 

 minent, largest about the middle of the whirl, fine at the base ; suture profoundly 

 impressed. 



MAZZALINA, Conrad. 



Turbinate, smooth; columella projecting interiorly and furnished with closely 

 arranged, oblique, obtuse plaits. 



Mazzalina pyrula. Pyriform, moderately thick in substance; spire conical, 

 whirls carinated below the suture ; columella with eight plaits ; beak slightly recurved ; 

 labrum with prominent, acute lines within. 



Leno-th 1J inches. Diameter 1 inch. 



LEDA, Shum. 



Leda eborea. PI. 47, fig. 26. Triangular, equilateral, ventricose smooth polished ; 

 lunules of equal length and defined by carinated lines ; anterior lunule widely 

 elliptical ; dorsal margin when the valves are together defined by a slight carina ; 

 a slight furrow near the posterior dorsal margin and parallel with it ; posterior end 

 acutely rounded and the submargin slightly contracted ; base regularly rounded. 



Length % inch. 



Leda bella, Conrad. A variety of this Claiborne species accompanies the pre- 

 ceding. The concentric lines are less conspicuous', and the transverse wrinkles on 

 the upper anterior side which are so prominent in the Claiborne shell are obsolete 

 in this. 



AXINiEA, Poll. 



AxiNiEA bellasculpta. Suborbicular, convex, equilateral ; radii in the middle of 



the disk trilineate, radiating lines conspicuous to the margins, anteriorly somewhat 



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