NORTH-CAROLINA GEOLOGICAL SURVEY. 247 



per part of the formation associated with sharks' teeth, and 

 teeth and stings of one or two species of ray. 



CLASS GASTEROPODA. FAMILY MURICIDAE. 



The muricidae are generally readily distinguished by their 

 roughness occasioned by the periodical expansion of its lip. 

 These being permanent, the shell is strongly marked by the 

 rough shelly expansions along the lines of growth, as in the 

 murex. The shell preserves its spiral form ; the outer lip is 

 entire behind, and the front prolonged in a straight canal. 

 The eyes of this family are sessile and seated on tentacles ; 

 the animal has a broad foot. 



GENUS MUREX. LINN. ROCK SHELL. 



The shell is roughened, or winged with the periodical ex- 

 pansions of its lip, which are permanent after it has advanced 

 to a mature state. 



MUREX UMBRIFER CON. CERASTOMA UMBRIFER TOUMEY AND 



HOLMES FOSSILS SOUTH-CAROLINA FROM CON. MSS. (Fig. 104a. ) 



FIG. io4a. Shell fusiform ; whirl? 



subcari nated, or angulat- 

 ed and provided with 

 six foliated and rather 

 broad renexed lamina, 

 spirally arranged. Mi- 

 ocene Cape Fear River. 



MUREX GLOBOSA. (Fig. 105 A.) 



Shell rather globose, or obtusely fusiform, and with four 

 principal varices ; intermediate ones irregular and spirally, 

 traversed by many angular ridges, body whirl inflated, aper- 

 ture oval, peristome continuous, and extended posteriorly on 

 the body whirl, forming an angulated canal ; outer lip ridged 

 within and crenulated on the margin ; collumela lip ridged. 



