210 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
uniform prominent threads on the upper half of the last whorl and between 
the sutures of the spire, with wider interspaces; on the base the threads 
are more numerous, smaller, and with subequal interspaces, extending from 
near the periphery to the umbilicus, which is perforate and not internally 
sculptured; axial sculpture of fine regular incremental lines not modifying 
the spirals; aperture rounded-quadrate, simple, sharp-edged, the lips con¬ 
nected by a glaze on the body, not anywhere reflected; height, 3; larger 
diameter, 3.2 mm. (Dali.) 
Type in United States National Museum, No. 208559. Type locality, 
Granite Cove, Port Althorp, Alaska, 14 fathoms. 
Range. Known only from type locality. 
Subgenus Margarites Leach, s.s. 
Margarites helicina Phipps, 1773 
Voyage to the North Pole, Appendix, 198. Binney’s Gould, Report on the Invcrte- 
brata of Massachusetts, 281, fig. 542. 
Testa umbilicata convexa obtusa: anfractibus quatuor laevibus. 
(Phipps.) 
Shell small, orbicular, depressed, thin, and translucent, smooth and 
shining, of a light yellowish horn color or light olive; whorls four or five, 
very convex, the last very large and tumid, a little flattened above; 
minutely wrinkled by the lines of growth, and at its base marked with very 
fine spiral lines; suture well-impressed; aperture large, circular, somewhat 
expanded; edge sharp and simple, a little reflected at the umbilicus, which 
is large and profound, not bounded by an angular ridge; operculum horny, 
multispiral. Length, one-fifth of an inch; breadth, nearly three-tenths of 
an inch. (Binney and Gould.) 
Type in ? Type locality, north side of Spitzbergen. 
Range. Bering Strait, all coasts of Bering Sea, to Catalina Island, 
California. 
Margarites helicina excavata Dali, 1919 
Proceedings of the United States National Museum, 56:366. 
Shell small, depressed, thin, polished, lurid flesh color with a darker 
globular glassy nucleus, and about three subsequent whorls, on which a 
few spiral lines of obscurely lighter color are sometimes apparent; suture 
distinct, not appressed; surface with faint incremental lines as the only 
sculpture; base rounded with, in the adult, a widely excavated funicular 
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