80 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Cythna albida Carpenter, 1864 
Proceedings of the California Academy of Sciences, 3 :219. 
C. t. minuta, albida, laevi, diaphana, lata; anfr. nucl. normalibus, ver- 
tice mamillato; norm. iii. tumidis, rotundatis, rapide augentibus suturis 
valde impressis; basi rotundata, valde umbilicata; umbilico subangulato; 
apertura subrotundata; peritremati continuo, acuto, t. adulta nonnunquam 
a partiete separato. (Carpenter.) 
Shell minute, whitish, smooth, transparent, broad; with normal nuclear 
whorls, vertix mammillate; normally three tumid, rounded, increasing 
rapidly, with sutures strongly impressed; base rotund, strongly umbilicate; 
with subangular umbilicus; aperture subrotund. (Translation.) 
Type in ? Type locality, San Pedro, California. 
Range. Southern California, parasitic on starfish. 
Genus HALIELLA Monterosato, 1873 
Melanellids in which the inner lip is provided with a twist which gives 
it the appearance of having an obsolete fold. (Bartsch.) 
Type. Haliella stenostoma A. Adams. 
Distribution. West coast of America; Japan. 
Haliella abyssicola Bartsch, 1908 
Proceedings of the United States National Museum , 53:336; PI. 48, fig. 8. 
Shell elongate-conic, straight, semi-transparent, polished, bluish-white, 
marked by scarcely perceptible lines of growth. Whorls slightly rounded, 
rather high between the sutures; the appressed portion of the summit ap¬ 
pearing as a narrow white band, the posterior limit of which forming the 
suture is scarcely perceptible since it practically fuses with the preceding 
turn. Periphery of the last whorl well-rounded. Base moderately long, 
well-rounded. Aperture very large, ear-shaped; posterior angle acute; 
outer lip very thin, becoming gradually protracted from the posterior 
angle to the periphery, then more rapidly retractive toward the base, basal 
portion of the outer lip forming a broad, rounded channel; inner lip long, 
decidedly sigmoid, slightly reflected and partly appressed to the base, pro¬ 
vided with a twist a little anterior to its insertion; parietal wall covered 
with a thin callus. Length, 10.4; diameter, 2.9 mm. (Bartsch.) 
Type in United States National Museum, No. 251266. Type locality, 
United States Bureau of Fisheries Steamer “Albatross” Station 2923, off 
southern California. 
Range. In 822 fathoms off San Diego, California, to off Point Pablo, 
Lower California, in 284 fathoms. 
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