92 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Alvania filosa Carpenter, 1865 
Annals and Magazine of Natural History , series 3, 14: 7. Proceedings of the United 
States National Museum, 41:342; PI. 30, fig. 7. 
A. testa A. reticulatac indole et colore, haud sculptura, simili; multo 
majore, elongata; anfr. nucl.? . . . (detritis), norm. iv.; striis parum 
separatis circ. xviii. (quorum circ. xii. in spira monstrantur) cincta; 
rugalis radiantibus posticis creberrimis, haud expressis, circa peripheriam 
evanidis; peritremate continuo; columella rufo-purpureo tincta. Long., 
.13; long, spin, .09; lat., .06 poll. (Carpenter.) 
Shell elongate-conic, thin, translucent, yellowish-white. Nuclear whorls 
one and one-half, well-rounded, smooth. Post-nuclear whorls well- 
rounded, roundly shouldered at the summit, marked by slender, feebly 
developed, sinuous, axial riblets. In addition to these riblets, the whorls 
are marked by equal and equally spaced, spiral cords, which are equal to 
the riblets in strength. Of these cords 10 occur between the sutures on the 
antepenultimate, and 12 on the penultimate turn. The spaces inclosed be¬ 
tween the spiral cords and the axial ribs are shallow, impressed, squarish 
pits. Suture strongly constricted. Periphery and the rather short base of 
the last whorl well-rounded; the latter very narrowly umbilicated, marked 
by eight equal and equally spaced spiral cords, which are a little wider than 
the spaces that separate them. The sulci between the spiral cords on the 
base are crossed by the feeble extensions of the axial riblets. Aperture 
broadly oval ; posterior angle obtuse ; outer lip thin, showing the external 
sculpture within; inner lip moderately stout, curved and reflected, the 
posterior half appressed to the base; parietal wall covered with a thick 
callus, rendering the peritreme complete. Length, 3.5; diameter, 1.7 mm. 
(Bartsch.) 
Type in United States National Museum, No. 36632. Type locality, 
Neah Bay, Washington. 
Range. Known only from type locality. 
Alvania alaskana Dali, 1886 
Proceedings of the United States National Museum, 9:307; PI. 4, fig. 9. 
Shell very elongate-ovate, white. Nuclear whorls one and one-half, 
strongly rounded, very finely papillose. Post-nuclear whorls strongly 
rounded, appressed at the summit, marked by fairly strong, spiral cords, 
of which three occur upon the first whorl, so arranged that the first below 
the summit marks the anterior termination of the posterior third between 
the sutures; the other two divide the space anterior to this into equal parts. 
The spaces separating these cords are a little narrower than the cords. On 
the second whorl an additional cord makes its appearance halfway be- 
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