NATURAL SCIENCES OP PHILADELPHIA. 285 



it is probable that all of this family", recent and fossil, in America belong to 

 distinct genera, usually classed as subgenera by autbors. The predominant 

 forms in the Miocene of the United States are Drillia and Surcula, the latter 

 containing some species much larger than any of the former genus. The true 

 Turris group is also absent from the Eocene, where species of the two Miocehe 

 genera above mentioned and others abound. It is also unknown in a recent 

 state on the American coasts. 



SURCULA, Gray. 



1. Surcula e n g o n a t a. Fusiform ; whorls 8, turrited, nodulous on the 

 angle, very minute revolving lines above the angle, distinct below it ; one line 

 more prominent near and below the suture ; labrum margin rounded ; body 

 whorl with obsolete revolving lines. 



Locality. Virginia. 



2. Surcula nodu lifer a. Subfusiform, turriculate ; whorls 8, carinated 

 below the suture by a subtuberculous line, and furnished with tubercles 

 shaped like inverted commas, distant ; a revolving line between the tubercles 

 and suture ; body whorl with prominent revolving lines and a minute inter- 

 mediate one. 



Locality. Virginia. 



3. Surcula ru g a t a. Fusiform, turriculate ; whorls 10, lower half obtusely 

 ribbed ; upper half concave, subangular, with much curved, rugose lines of 

 growth ; beneath the suture whorls obtusely subcarinated, distinct revolving 

 lines over the ribbed portion, minute and obsolete above it ; suture profound ; 

 body whorl and beak striated ; beak slightly curved. 



Locality. Calvert Cliffs, Md. 



DRILLIA, Gray. 



1. Drillia impress a. Elevated, scalariform or turriculate, with short, 

 obtuse ribs ; contractions of whorls striated, and having a carinated line 

 near the suture, revolving lines impressed, double, alternated, rugose volu- 

 tions 8 ; base subumbilicated. 



Locality. James River, Virginia. 



2. Drillia d i s t a n s, n. s. Turriculate, whorls 6, scalariform, with distant 

 obtuse ribs on the lower half; suture waved, with an impressed line above it ; 

 body whorl with an impressed revolving line above and' four raised revolving 

 lines inferiorly ; upper sinus of labrum deep and rounded, lower obsolete. 



Locality. Virginia. 



3. Drillia arata. Turriculate, whorls 9; spire elevated, acute: subsca- 

 lariform, the contracted portion of the whorls flattened and with perpendicular 

 sides, below this space costate, ribs somewhat oblique and crossed by minute, 

 close lines, which on the body whorl reach the base, obsolete above, distinct 

 inferiorly. 



Locality. Virginia. 



4. Drillia bell a. Turriculate ; whorls 7, scalariform, costate nearly to 

 the suture ; ribs distant, obtuse ; whole surface with minute revolving raised 

 lines, very minute and close on the contracted space below the suture, reflected 

 labrum callous at the upper end. 



Locality. Virginia. 



5. Drillia e b u r n e a. Turrited ; upper part of whorl without ribs and with 

 an impressed revolving line ; lower part ribbed, ribs oblique, rounded ; surface 

 striated with close impressed revolving lines, finer and obsolete on the upper 

 part of the whorls. 



1862.] 



