26 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
six or seven to a whorl, angular but not very prominent, except on the 
angle, where they are sometimes prolonged into long recurved processes, 
in other cases only making a prominent angular tubercle; the whole 
surface is covered with strong revolving ribs, crossed by fine squamose 
plates; aperture subelliptical, lips prominent, white within, the outer lip 
with five or six tubercles internally, last varix forming a broad lateral 
expansion to the lip; canal closed, straight, or more usually a little re¬ 
curved. (Gabb.) 
Length, 20 mm. (Oldroyd.) 
Type in Survey Cabinet, Mollusca, Nos. 515 b, c, and d . Type local¬ 
ity, Catalina Island, California, in 40 fathoms. 
Range. British Columbia to Catalina Island, California. 
Described as Murex barbarensis . 
Tritonalia epiphanea Dali, 1919 
Proceedings of the United States National Museum , 56:335. 
Shell small, dark brown, acute, with an angular shoulder, slender, 
with six whorls exclusive of the (lost) nucleus; suture distinct slightly 
wrinkled and more or less appressed; spiral sculpture of (on the penul¬ 
timate whorl, six above and seven below the shoulder) strong equal 
threads with narrower interspaces, the whole slightly imbricated and 
covering the entire surface in a regular manner; axial sculpture of (on 
the last whorl, seven) strong rounded ribs most prominent at the shoul¬ 
der and with much wider interspaces, the spire deeply constricted at the 
suture; aperture oval, the outer lip thickened but not reflected, internally 
white with six equal and equally spaced denticulations, the body and 
arcuate short pillar with a layer of white enamel; the canal long, closed 
near the aperture, with a narrow fasciole and slightly recurved. Height 
of shell, 25 ; of last whorl, 18; of aperture and canal, 13; diameter, 11 mm. 
(Dali.) 
Type in United States National Museum, No. 216809. Type locality, 
San Pedro, California. 
Range. San Pedro and Catalina Island, California. 
Tritonalia tracheia Dali, 1919 
Proceedings of the United States National Museum, 56:335. 
Shell small, solid, rough, of a greenish-gray color, of about five 
strongly shouldered whorls, the nucleus lost; the suture obscure, not 
appressed; axial sculpture of (on the penultimate whorl nine, on the 
last whorl six or seven) strong ribs, subspinose at the shoulder, and 
extending to the base; beside these there are rude incremental lines; 
spiral sculpture on the spire of two strong cords at the periphery, nodu- 
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