52 AMERICAN MARINE CONCHOLOGT. 



interstices darker, suture porcellanous, last whorl numerously 

 fasciate. 



Length 10, diam. 4.5 mill. 



Oak Island, North Carolina. 



This species I have not seen, and it has not been figured. 



2. M. FILIFORMIS, Holmes. Fig. 86. 



Post-Pliocene Foss. So. Car. 69, t. 11, f. 9. 1860. 

 Shell fusiform, costate, transversely striate; costae smooth, 

 somewhat angulated at the periphery of the middle whorls ; the 

 third whorl cancellate; apex smooth; base without ribs; striae 

 transverse, numerous, slightly waved, filiform. 



South Carolina. 



In general outline this little shell resembles the young of Fusus 

 cinereus. Say, but the smooth ribs, nodulous and angulated peri- 

 phery of the middle whorls and beautiful filiform striae, readily 

 distinguish it from that species. 



3. M. LABECULA, Gould. 



Proc. Bost. Soc. Nat. Hist., viii. 281. 1862. 



Shell small, ovate fusiform, waxy, with chestnut markings 

 within and without the lip, thinly spiralty striate, with sixteen 

 longitudinal plications which become evanescent on the body- 

 whorl ; whorls seven to eight with a subsutural impressed line ; 

 aperture small, oval ; lip gibbous, thickened without and granu- 

 late within. Sinus scarcely perceptible. 



Length 7, diam. 3 mill. 



(Dredged. ) Coast of Georgia. 



Family YOLUTIDJ3. 



Shell turreted or convolute ; aperture notched in front ; colu- 

 mella obliquely plaited. No operculum (typically). Animal with 

 a recurved siphon ; foot very large, partly hiding the shell ; man- 

 tle often lobed and reflected over the shell, eyes on the tentacles 

 or near their base. 



Synopsis of Genera. 



Shell ventricose, thick ; spire short, apex mammillated ; aperture large, 

 outer lip not thickened, deeply notched in front ; columella with several 

 plaits. YOLUTA, Linnaeus. 



Shell fusiform, thick ; spire elevated, acute ; aperture small, notched in 

 front ; columella obliquely plaited ; operculum very small. 



MITRA, Humphreys. 



