HELICIDA. 5 51 
Anctus, Albers, 1860. Shell rimate, ovate-conical, thin, striate, 
white, strigate with brown; whorls seven, rather flat, the last 
compressed in front; aperture narrowly oblong, vertical, peris- 
tome shortly reflected, the margins parallel. B. anchixtoma, 
Wagner (xeviii, 29). Brazil. 
Mesembrinus, Albers, 1850. Shell subimperforate, or perfor- 
ation covered, oval-conic, longitudinally striate or a little rugose; 
whorls six or seven ; aperture oval-oblong ; columella subtortu- 
ous 3 peristome simple, shar p; columellar lip more or less dilated, 
reflected. £B. virgulatus, Fer. (xeviii, 30). 81 sp. Lower Cali- 
fornia, Mexico, Florida, W. Indies, Central and So. America. 
Mormus, Albers, 1860. Shell rimate, oblong-conical, striate 
or costulate, thin, white, usually fuscously variegated ; whorls 
six or seven, the upper ones somewhat flattened, the last rather 
tumid; aperture about half the length of the shell, subovate ; 
peristome simple, the columellar margin dilated and reflected. 
B. papyraceus, Mawe (xeviii, 32). 43 sp. L. California, Mexico, 
Central and South America. 
Scuta‘us, Albers, 1850. Shell perforated or umbilicated, 
oval-conic, striated, granulated, somewhat hirsute; whorls 
4-7, the last ventricose, somewhat narrowed at the base; 
aperture oblong-oval; peristome expanded, usually reflected, a 
little thickened within. B. thamnoicus, d’Orb. (xevili, 33). 28 sp. 
L. California to So. America. 
Pyrgus, Albers, 1850. Shell turreted; whorls nine, the last 
being a third of the total length; aperture oval ; peristome 
simple, thin; columellar lip reflected above. AB. tur r itus, Brod. 
Peru. 
Ataxus, Albers, 1850. Shell umbilicated, oval-conic ; whorls 
six, the last compressed and angular around the umbilicus, which 
is very large ; aperture narrow, oblong, subangular at the base, 
about one-third the length of the shell; peristome simple; lips 
closely approaching at their extremities ; columellar lip str aight, 
expanded above. B. umbilicaris, Soul. (xevii, 21). 5 sp. So. 
America. 
Hurytus, Albers, 1850. Shell imperforate, thin, oval-oblong ; 
whorls four or five; aperture rather longer than the spire, 
oblong-oval; columella arcuated; peristome subreflected ; lips 
united by a thin callus. B. Cathcartix, Reeve (xeviii, 25). 33 
sp. South America. 
Oxycheilus, Albers, 1350. Shell thin, pellucid, shining, sub- 
imperforate, subfusiform, apex acute; whorls six or seven; 
aperture oblong-oval, shorter than the spire; columella nearly 
straight, slim; peristome simple; columellar lip reflected. B. 
Hanleyi, Pfr. (xuvii, 17)... Brazil. 
Peronxus, Albers, 1850. Shell perforated or fissured, oblong- 
turreted or subulate; whorls 8-1], convex; aperture oblong or 
