142 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Turbonilla castanea Keep, 1888 
Plate 53, figs. 1, la; Plate 66, fig. 7 
West Coast Shells, 52; fig. 33. Bulletin 68, United States National Museum, 101; 
PI. 9, figs. 1, la. 
Shell is somewhat larger than that of the last (C. torquata Gould), 
and is of a chestnut color. Its eight or ten whorls are marked with nu¬ 
merous fine ribs, and though so small, it is a beautiful shell. (Keep.) 
Shell elongate-conic, chestnut-brown. Nuclear whorls very small, two 
and one-half, depressed, helicoid, having their axis at right angles to that 
of the succeeding turns, in the first of which they are about one-fourth 
immersed. Post-nuclear whorls flattened in the middle, slightly excurved 
at the summit, where they are faintly shouldered and somewhat contracted 
at the periphery, marked by rather irregular, strong, low, rounded, retrac¬ 
tive, axial ribs, of which 20 occur on the third, 22 on the fourth, 24 on the 
fifth to seventh, 26 on the eighth; 28 on the ninth, and about 50 upon the 
penultimate whorl; upon this they are very irregular. Intercostal spaces 
less wide than the ribs, shallow, marked by a series of spiral pits, which 
vary in width and number on the various whorls; on the early ones there 
are eight, on the ninth there are twelve, while on the penultimate there are 
sixteen between the peripheral series and the summit. Sutures well-marked. 
Periphery and base of last whorl inflated, marked by the continuations of 
the axial ribs, which extend almost undiminished to the umbilical area; 
and about twenty, subequal and subequally spaced, incised, spiral lines. 
Aperture pear-shaped; posterior angle acute; outer lip thin, showing the 
external sculpture within; chestnut-brown; columella slender, strongly 
curved, and slightly revolute; parietal wall covered by a thick callus. 
Length, 10.5; diameter, 2.5 mm. (Bartsch.) 
Specimens in United States National Museum, No. 160224. Specimens, 
San Diego, California. Type locality, San Diego, California. 
Range. San Pedro to San Diego, California. 
Turbonilla wickhami Dali and Bartsch, 1909 
Bulletin 68, United States National Museum, 106; PI. 10, fig. 9. 
Shell elongate-conic, milk-white. (Nuclear whorls decollated.) Post- 
nuclear whorls flattened in the middle, contracted at the sutures, with a 
moderately broad, sloping shoulder at the summit, marked by well-de¬ 
veloped, rounded, very regular, slightly protractive axial ribs, of which 20 
occur upon the second and 22 upon the remaining, excepting the penulti¬ 
mate whorl, which has 32. Intercostal spaces a little wider than the ribs, 
marked by seven series of spiral pits, of which the third below the summit 
is almost twice as wide as the rest. Sutures moderately constricted. 
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