17 



PECTUNCULUS PULVINATUS, Tab. 2, fig. 2. 



Orbicular, convex, subequilateral, with numerous radiating 

 striae ; beaks small, central ; hinge edentulous in the centre ; in- 

 ner margin with approximate angular lines or teeth. 



Localities. York Town, Suffolk, Va. Upper Tertiary. 

 Syn. PECTUNCULUS PULVINATUS, Lam. An. sans Vert. vol. 6. 

 p. 04. 



This shell is very common in France .and Italy. Lamarck 

 describes three varieties, and observes that he believes it to be 

 anologous to P. glycimeris. 



In the vicinity of York Town, it is washed out of the high 

 sandy banks, accompanied by the following species, from which 

 it can. always be distinguished by its orbicular form, &c. 



PECTUNOULUS SUBOVATUS, 'Tab. 2, fig. 3. 



Suborbicular or sobovate ; inequilateral ; with radiating sulci, 

 becoming obsolete with age ; 'hinge, with the series of teeth cut 

 off, and nearly obliterated in the centre, by a rectilinear line ; 

 teeth largest on the shorter side of the valve ; marginal teeth 

 broad and separated. 



Syn. PECTUNCULUS SUBOVATUS, Say. Journ. A. N. S. v. 4, p. 

 PECTUNCULUS VARIABILIS? Sow. Min. Con. v. 5, t. 471. 



Localities. York Town, abundant ; Suffolk, Va. Upper Ter. 



If this should prove to be identical with P. variabilis, it will 

 be an interesting species in consequence of its being character- 

 istic of the same formation in Europe and America. 



MUREX UMBRIFER. Tab. 3. fig. 1 . 



Fusiform, with 6 foliated reflected laminae ; whorls angular 

 and carinated ; aperture obovate; beak recurved. 



Localities. James River ; York Town. Va. Upper Tertiary. 



FUSUS EXILIS. Tab. 3, fig. 2. 



, Fusiform, elongated, with longitudinal undulated ribs, and 

 revolving*strii*3, acute, elevated and alternately smaller; beak 

 produced, nearly straight ; aperture half the length of the shell. 

 Locality. James River. Va. Upper Tertiary. 



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