.MAltVI.AM) CKOI.OCIC \r, SI'ItVICY 143 



spaces; lines of grdwtli somrw liiit irrc^iulai-; (■■•iiial iMtluT Ion*,', iiaiTow." 

 Clark, ISOC. 



This species tlilTer- rniiii /•'. Iriscrialis WliiUield in having the three 

 I'ows (if tiiheriles of nearly e([iial strength, and spacerl at nearly equal 

 distances, in lia\iii^ more elevated ^piic. ami in liaviiiL:' that iiortion ol' 

 the l)()(ly wlidi'l, <>r wliieli I he middle row id' I nljei-elfs is in tlie center, 

 niiiforndy cdnNcx I li I'onuhnid, iiisU'ad of sharply angnhitod at the 

 slioiddei- and nearly Hal lielow. 



Leni^lh, "iT nun.; \\idlli, IS mm. 



Occurrence. — Nanjemoy Formatiox. Woodstock. Aquia Fok.ma- 

 Tiox. rotoniac Ci'cek, 2 nules Leldw rotomac Crock. Poiiionkcy Neck, 

 Upper Marlboro. 



Collections. — IMai'yland Coologieal Sni'vey, T". S. Xational ^Iiiseum, 

 Philadelpliia Academy of Natural Sciences, Johns Hopkins University. 



Genus FUSOFICULA Sncco. 



FusoFicuLA JUVEXis (Whitfield). 



Plate XXIA^ Figs. 4, 4a. 



Pi/ruln jiiveuis Whitfield, 1865, Amer. Jour. Conch., vol. i, p. 3ot). 



Fusoflcula Juve/iia Harris, 18t)tt, Bull. Amer. Pal., No. 11, p. 60, pi. viii, fiirs. 1.5, 16. 



Descripiion. — " Shell small and fragile; spire elevated; columella 

 slender, slightly bent; aperture large, elongate, ovate or .sub-elliptical; 

 volutions three; marked on the periphery by three distinct carinae or suli- 

 angular revolving ridges, the upper one marked with closely arranged, 

 longitudinally elongated nodes, the others simple; entire surface marked 

 by very fine revolving lines, which are somewhat fasciculate below the 

 lower carina, there being three finer ones between each large one." 

 Whitfield, 1865. 



A single specimen of typical form and excellent state of preservation 

 was found. 



Length, 23 mm.; width. 11 mm. 



Occurrence. — Aquia Foematiox. 2 miles below Potomac Creek. 



Collect ion. — ^Maryland Geological Survey. 



