20 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
montereyense the variegated forms predominate; that is, the shells are 
whitish, mottled with rust brown. Length, 13.8; diameter, 5 mm. 
(Bartsch.) 
Type in United States National Museum, No. 32221. 
Range. Crescent City, California, to Cape San Lucas, Lower Cali¬ 
fornia. Pliocene, California. 
Bittium paganicum Dali, 1919 
Proceedings of the United States National Museum, 56:345. 
Shell small, slender, dark reddish brown, more or less divided by paler 
spiral lines on the later whorls; smooth except for incremental lines, with 
more than six rather flattish whorls, the apex in every case eroded; suture 
distinct, not deep; base rounded, imperforate, the aperture ovate, the outer 
lip thin, sharp, somewhat arcuate, and produced anteriorly; inner lip 
erased; pillar lip slightly twisted, not thickened; operculum paucispiral. 
Height, 8; diameter at truncation, 1.5; at base, 3 mm. (Dali.) 
Type in United States National Museum, No. 271078. Type locality, 
U.S. Fish Commission, Station 4508, nine miles off Point Pinos, Monterey 
Bay, California, in 356 fathoms. 
Range. Known only from type locality. 
Subgenus Semibittium Cossmann, 1896 
Bittium vancouverense Dali and Bartsch, 1910 
Canada, Department of Mines, Geological Survey Branch, Memoir No. 14-N, 1910, 10; 
PI. 1, fig. 8. 
Shell elongate-conic, grayish white outside and dark, purplish brown 
within. Nuclear whorls at least two, apparently smooth, worn in all speci¬ 
mens. Post-nuclear whorls slightly rounded, ornamented with three strong, 
equal and equally spaced, nodulose, spiral keels, the first of which is a little 
below the summit. The spaces separating the spiral keels are of equal 
width. Immediately below the third keel is a strong, peripheral sulcus, 
which equals those between the spiral keels. In addition to the spiral 
sculpture, the whorls are marked by almost vertical, axial ribs, which are 
not quite as wide as the spiral keels. These render the keels nodulose at 
their intersections. Of these ribs, 12 occur upon the first, 14 upon the 
second and third, 16 upon the fourth, 18 upon the fifth, 24 upon the sixth, 
and 30 upon the penultimate turn. The spaces inclosed between the spiral 
keels and the axial ribs are well-impressed, rounded pits. All the tubercles 
are truncated on the posterior margin and slope gently anteriorly. Base of 
the last whorl moderately long, ornamented with seven spiral cords, of 
which the two immediately below the periphery are the strongest and 
broadest, while the two bounding the umbilical area are wider than those 
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