24 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
suture obscure, undulated; axial sculpture of (on the last whorl, 8; on 
the penultimate, 10) low, inconspicuous, rounded ribs extending more or 
less distinctly to the canal with continually wider interspaces; also low 
sharp incremental lines minutely imbricating the whole sculpture; spiral 
sculpture of (on the penultimate whorl, about seven; on the last whorl, 
about twenty-five) strong prominent cords with wider interspaces usually 
showing an intercalary thread which on the last whorl becomes nearly 
as strong as the others; aperture rounded, outer lip simple, periodically 
varicose; body erased, pillar straight; canal distinct, open, narrow, slightly 
recurved. Height of shell, 29; of last whorl, 21.5; of aperture and 
canal, 15; diameter, 16 mm. (Dali.) 
Type in United States National Museum, No. 222569. Type locality, 
near Port Townsend, Washington, in 20 fathoms. 
Range. Coast of Washington to Venice, California. 
Tritonalia subangulata Stearns, 1873 
Conchological Memoranda , Part XII, 5; PI. 1, fig. 4. 
Shell small, abbreviated fusiform, dingy white and marked spirally 
by an inconspicuous band formed of three reddish-brown lines more or 
less interrupted on the basal and the preceding volution; whorls five, 
angulated above and on the basal whorl rounded below the angle, with a 
shallow sulcation beneath; surface covered with rounded and irregular 
costae, which are inconspicuous or obsolete on the upper whorls; longi¬ 
tudinally marked with from seven to nine irregular rounded ribs, which 
at the edge of the angle (which is somewhat carinated) are broken 
into angular or pointed knobs or blunt spines; aperture ovate, angulated 
above and white within; the outer lip with five or six tubercles internally; 
canal moderately prolonged, slightly curved and open in the two specimens 
before me. Length, .89; lat., .41 inch. (Stearns.) 
Type in United States National Museum. Type locality, San Miguel 
Island, California. 
Range. Monterey to Santa Barbara Islands, California. 
Tritonalia michaeli Ford, 1888 
Proceedings, Philadelphia Academy of Natural Sciences, 1888, p. 188. 
Shell fusiform, rather slender, turreted, light gray, with a narrow 
median brown band; whorls five, convex, shouldered above, the upper 
ones carinate; sculptured with numerous rather coarse revolving lirations, 
the interstices with riblets bearing crowded festooned lamellae of growth, 
which are also prominent below the suture; longitudinally prominently 
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