MARINE MOLLUSCA OF THE UNITED STATES. 49 
Shell turriculated, thin, with seven or eight shouldered whorls, 
apex acute; surface with twelve to fourteen oblique, compressed 
ribs, becoming obsolete below the middle of the body-whorl, and 
numerous, elevated, spiral lines ; cuter lip sharp, canal short, open, 
columella smooth, arcuate. White or yellowish. 
Length 16, diam. 6 mill. 
Massachusetts and northwards ;. England. 
Differs from the next species by being broader, more delicate, 
and by its angulately shouldered whorls. 
2. B. HARPULARIA, Couthouy. Fig. 81. 
(Fusus.) Bost. Journ. Nat. Hist., ii. 106, t. 1, f10. 1888. 
Shell ovate-oblong ; whorls six to eight, round-shouldered, with 
about eighteen oblique rounded ribs, crossed by fine revolving 
lines, ribs becoming obsolete on lower part of body-whorl. Brown- 
ish flesh color. Aperture narrow, outer lip sharp, inner lip white, 
smooth, moderately arched, canal very short. 
Length 12, diam. 6 mill. 
Massachusetts, northward. (Eur.) 
It is constant in its color, which differs from both the preceding 
and following species. 
3. B. PLEUROTOMARIA, Couthouy. Fig. 82. 
(Fusus.) Bost. Journ. Nat. Hist., ii. 107, t. 1, f. 9. 1838. 
Fusus rufus, Gould (non auct.), Invert. Mass. 1st edit. 290. 1841. 
B. pyramidalis, Strom. 
B. Vahlii, Beck. 
Shell elongated-fusiform, apex acute; whorls eight, slightly 
convex, with eighteen to twenty undulating longitudinal ribs and 
equal interstices covered by very fine spiral striz ; body-whorl 
more than half the length of the shell, slightly shouldered, the 
ribs obsolete, but spiral striz more conspicuous on the lower por- 
tion; aperture small and narrow, canal very short; reddish-fawn 
colored. 
Length 12, diam. 3.25 mill. 
Cape Cod, Mass., northward. 
4. B. CANCELLATA, Mighels and Adams. Fig. 83. 
(Fusus.) Bost. Journ. Nat. Hist., iv. 52, t. 4, f. 18. 1842. 
Shell turreted, slender; with seven convex whorls, decussated 
by twenty longitudinal ribs crossed by numerous raised revolving 
lines, giving the surface a cancellated appearance; spire acumin- 
d 
