122 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
shell, and in some cases there is a specimen on both valves of the Glottidia. 
(Dali.) 
Type in United States National Museum. Type locality, San Pedro, 
California. 
Range. Known only from type locality. 
Family NATICIDAE 
Genus NATICA Scopoli, 1777 
Shell oval globular, porcellanous, solid, generally smooth, covered by 
a fine epidermis, which is transparent, and generally not very persistent ; 
umbilicated, or umbilicus more or less filled with callus; aperture 
semilunar, vertical, the outer lip simple. Operculum large, semilunar, 
paucispiral, corneous or calcareous. (Tryon, Manual of Conchology.) 
Type. Natica canrena Linnaeus. 
Distribution. Warm seas in all quarters of the globe. 
Subgenus Cryptonatica Dali, 1892 
Natica clausa Broderip and Sowerby, 1829 
Plate 97, fig. 2 
Zoological Journal, 4:372. Tryon, Manual of Conchology, 8: Pi. 9, fig. 65. 
N. testa subglobosa, anfractibus ventricosis, superne subdepressis, mar- 
gine elevatiusculo; umbilico clauso. Long., 10/20; lat., 17/20 poll. (Bro¬ 
derip and Sowerby.) 
The umbilical callus completely covers the umbilicus. Operculum tes¬ 
taceous, rather thin and somewhat concave. (Broderip and Sowerby.) 
Type in Sowerby Collection. Type locality, Arctic. 
Range. Arctic and Bering Seas to San Diego, California; also Japan. 
Natica affinis Gmelin, 1792 
Systema Naturae, 7:3675. Sars, Mollusca regionis arcticae Norvcgiac, PI. 21, fig. 14. 
N. testa globosa crassiore: spira submucronata; anfractibus tribus. 
(Gmelin.) 
Shell globose, somewhat thick; spire submucronate; three whorls. 
(Translation.) 
Type locality, habitat in Oceano septentrionali, an bujus tribus. 
Range. Arctic Ocean north of Bering Strait. Also Greenland. 
[7241 
