72 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Family LITIOPIDAE 
Genus LITIOPA Rang, 1829 
Shell minute, pointed; aperture slightly notched in front; outer lip 
simple, thin; inner lip reflected; operculum spiral. (Woodward, Manual 
of the Mollusca.) 
Type. Litiopa bombyx Rang. 
Distribution. Atlantic, Pacific, and Mediterranean, on floating sea¬ 
weed, to which they adhere by threads. 
Litiopa bombyx Rang, 1829 
Annales dcs sciences naturellcs, 203. Tryon, Manual of Conchology, 9:283; PI. 53, 
fig. 74. 
Whorls about nine, slightly convex, toward the apex microscopically 
longitudinally costulate, other whorls very finely spirally striate; light 
yellowish brown, outer lip often bordered internally with black. Length, 
6 mm. (Tryon.) 
This is the description of Litiopa melanostoma Rang, 1829, which is 
given as equal to the above. 
Type in ? Type locality, Pelagic, southern. 
Range. Southern California to Gulf of California. Pelagic. 
Genus ALABA A. Adams, 1862 
Shell smooth, semipellucid, whorls sometimes with a few, irregular 
varices; outer lip thin, simple; aperture slightly emarginate anteriorly. 
(A. Adams.) 
Type. Alaba trivericosa C. B. Adams. 
Distribution. Japan, Australia, Mazatlan, West Indies, California, 
and Gulf of California. 
Alaba jeanettae Bartsch, 1910 
Proceedings of the United States National Museum , 39:155; figs. 3, 4. 
Shell elongate-conic, semitransparent, with strong varices scattered at 
irregular intervals. Nuclear whorls four, continuing the general outline 
of the spire, well-rounded, smooth except for very faint, slender, axial 
threads, which, in most instances, are only apparent at the summit of the 
whorls. Post-nuclear whorls well-rounded, appressed at the summit; the 
early ones smooth, the later ones marked by slender, incised, spiral lines, 
of which those on the anterior half of the whorls between the sutures and 
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