40 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
spiral sculpture of (on the early whorls, 4; on the penultimate whorl by 
intercalation, 8; on the last whorl, about 25) narrow cords with wider or 
subequal interspaces, increasing by intercalation until on the last whorl 
they become practically equal and mostly minutely imbricated; aperture 
ovate; outer lip thin, simple; body erased; canal long, narrow, recurved; 
axis minutely pervious, pillar short, gyrate. Height of shell, 30; of last 
whorl, 24; of aperture and canal, 19; diameter, 10.5 mm. (Dali.) 
Type in United States National Museum, No. 210087. Type locality, 
United States Fish Commission Station 4515, off Point Pinos, California, 
in 198 to 495 fathoms. 
Range. Known only from type locality. 
Trophon apolyonis Dali, 1919 
Proceedings of the United States National Museum, 56:337. 
Shell small, white, subturreted, with more than four whorls, the apex 
eroded, the suture distinct; axial sculpture of (on the last whorl, 13 to 15) 
sharp low varices with wider interspaces, sometimes feebly angular at the 
shoulder on the spire but on the last whorl the angle is blunted or obsolete; 
there is no spiral sculpture, and the incremental lines are not conspicuous; 
aperture rather wide, ovate white, the outer lip reflected at the varices; 
body and pillar with a coat of white enamel; canal narrow, slightly re¬ 
curved, rather long; the base of the last whorl gently constricted. Height 
of three whorls, 21; of last whorl, 17; diameter, 10 mm. (Dali.) 
Type in United States National Museum, No. 209303. Type locality, 
United States Bureau of Fisheries Station 4423, in vicinity of the Santa 
Barbara Islands, California. 
Range. Known only from type locality. 
Trophon tripherus Dali, 1902 
Plate 33, fig. 10 
Proceedings of the United States National Museum , 24:545. Bulletin 112, United 
State National Museum; PI. 15, figs. 8, 9. 
Shell small, thin, delicate, white, with a thin yellowish periostracuin 
and about five whorls; nucleus eroded in all specimens; early whorls tabu¬ 
lar, with about 14 low, sharp varices, sharply angulated, but hardly spinose 
on the shoulder, and growing feebler on the subsequent whorls; below the 
shoulder are three feeble spiral threads which slightly undulate the vari¬ 
ces , these threads grow feebler with age, and are hardly perceptible on the 
last whorl; aperture ovate, passing into the long, slightly twisted canal, 
which is strongly recurved; suture very distinct; outer lip thin, deeply 
flexuous behind; pillar thin, attenuated in front, twisted with a pervious 
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