84 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Aclis occidentalis Hemphill, 1894 
Zoe, 4: 395. Proceedings of the United States National Museum, 39; PI. 62, fig. 2. 
Shell small, turriculated, white, shining, transparent, consisting of 
about nine, rather flattish, convex whorls, with a single fine, revolving 
thread-like lirae above the periphery, and with very fine microscopic re¬ 
volving striae beneath, observable only with a good glass and light; suture 
deep; aperture subquadrate ; lip simple, acute; columella straight. Length, 
4; breadth, 1 mm. (Hemphill.) 
Type in Hemphill Collection (now at Stanford University). Type 
locality, San Diego, California. 
Range. Known only from type locality. 
Genus NISO Risso, 1826 
Shell turriculated, smooth, polished, apex very sharp; umbilicus per¬ 
forated or wide; aperture small, angulated above and below. (Tryon, 
Structural and Systematic Conchology .) 
Distribution. China, West America. Fossil: Eocene—Paris; and 
Cretaceous. 
Niso lomana Bartsch, 1917 
Proceedings of the United States National Museum, 53:350; PI. 49, fig. 4. 
Shell large, broadly conic, yellowish-white. Early whorls well-rounded, 
later ones flattened, separated by a decidedly channeled suture, narrowly 
shouldered at the summit and decidedly angulated at the periphery, marked 
only by feeble axial lines of growth. The summit of succeeding turns 
falls a little anteriorly to the angulated periphery and forms a channeled 
suture. Aperture of the type fractured. The type has lost the early whorls 
and the base. The nine whorls remaining measure: length, 14.5 mm. 
(Bartsch.) 
Type in United States National Museum, No. 211847. Type locality, 
United States Bureau of Fisheries Steamer “Albatross” Station 2901, in 
48 fathoms, off Santa Rosa Island, California. 
Range. Santa Rosa Island to Point Loma, California. 
Niso hipolitensis Bartsch, 1917 
Proceedings of the United States National Museum, 53:350; PI. 49, fig. 5. 
Shell very small, elongate-conic, narrowly umblicated. Tip yellowish- 
white, base white with a broad median brown band; anterior half of 
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