190 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
lirae. The last whorl is somewhat biangular at periphery, slightly convex 
beneath. Aperture nearly round, oblique; peristome thin, a trifle crenu- 
lated inside; the columella has a slight excavation, and is very bluntly 
nodulous near the base; its inner face is dark, pearly. Alt., 5; diam., S l / 2 ; 
alt., 7y 2 ; diam., 7 l / 2 mm. (Tryon and Pilsbry, Manual of Conchology .) 
Type in ? Type locality, San Pedro, California. 
Range. San Pedro to San Diego, California. 
Calliostoma turbinum Dali, 1895 
Plate 100, fig. 1 
Proceedings of the United States National Museum , 18:8; also 24; PI. 39, fig. 1. 
Shell small, margaritae-form, with six and a half rounded whorls; 
nucleus minute, white, smooth, of one whorl, followed by strongly sculp¬ 
tured, rather inflated whorls separated by an inconspicuous suture; sculp¬ 
ture on the spire of rather elevated, narrow, spiral ridges, of which the 
most posterior is always beaded, though the beading on the others fails on 
the apical whorls; in front of this ridge is a smaller one, then three, or on 
the last whorl five, subequal, larger ones, the third forming the periphery 
of the whorl, the suture being laid against the most anterior ridge; the 
base has about twelve, subequal, more crowded, spiral threads, faintly or 
not at all beaded, larger toward the axis; the body of the shell is of a 
nacreous waxen tint, with transverse flammules of dark brown, which 
articulate the spirals, are much fainter on the interspaces, but do not reach 
the base, on which the spirals are more or less articulate with reddish 
brown; the base is somewhat flattened, the periphery not keeled, the pillar 
short, white, with a minute umbilical chink; aperture subquadrate, nacre¬ 
ous, sulcate by the external sculpture; there is no projection at the distal 
end of the pillar. Ideight, 12; major diameter, 12.5 mm. (Dali.) 
Type in United States National Museum, No. 122578. Type locality, 
U.S. Fish Commission Stations 2902 and 2972, among the Santa Barbara 
Islands. 
Range. Point Conception to San Diego and the islands. 
Genus TURCICULA Dali, 1881 
Shell globosely conical, white, thin; umbilicus reduced to a chink under 
the thin callus of the upper part of the pillar lip; mouth rounded rectangu¬ 
lar, margins all thin; columella concave; outer surface with tuberculose 
ridges. (Tryon and Pilsbry, Manual of Conchology.) 
[792 ] 
