56 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Epitonium lowei Dali, 1906 
Plate 31, fig. 1 
Nautilus, 20:44. 
Shell small, conic, with five or more rapidly increasing whorls after 
the (lost) nucleus; color white, whorls very convex with deep sutures 
and a small, spiral umbilicus; there is no basal disk or cord; sculpture 
of about twenty-seven rather thick, strongly reflected, smooth, close-set 
varices, and very close, fine, spiral threads, covering the whorl between 
the varices, and separated by about equal sulci; aperture sub-circular, 
slightly higher than wide, the reflected margin wide at the outer lip, 
patulous at the inner base, narrow between the shoulder and the preceding 
whorl, and at the shoulder produced into a short, rather stout spine which, 
repeated on successive varices, coronates the whorls. Length of shell 
(without nucleus), 7.0; diameter, 4.0; maximum diameter of aperture, 
2.5 mm. (Dali.) 
Type in United States National Museum, No. 191548. Type locality, 
off Avalon, Catalina Island, California. 
Range. Known only from type locality. 
Epitonium cookeanum Dali, 1917 
Proceedings of the United States National Museum, 53 :475. 
Shell small, pink, solid, acute, imperforate, the nucleus lost, with 
eight, well-rounded, subsequent whorls; with ten, rather solid, smooth, 
continuous, white varices, making less than half a turn round the spire; 
spiral sculpture of extremely fine uniform threads covering the whorl 
between the varices; the terminal varix thicker than the others; all the 
varices broader at the intersection with the suture but not spinose. Length, 
9.5; diameter, 4 mm. (Dali.) 
Type in United States National Museum, No. 211019. Type locality, 
San Diego, California? 
Range. San Diego, California, to Gulf of California. 
Epitonium lagunarum Dali, 1917 
Proceedings of the United States National Museum, 53:477. 
Shell small, thin, white, with six rounded whorls exclusive of the 
(lost) nucleus; varices sixteen, low, narrow, widely spaced, passing over 
the entire whorl; spiral sculpture of extremely fine striae, with a single 
thread on the periphery and a stronger one, marginating the imperforate 
base, on which the suture is laid; aperture obliquely ovate, the margin 
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