CLASS GASTROPODA 
95 
Range. Lower California, Gulf of California. 
This was described as Chemnitsia mnricata. 
Subgenus Strioturbonilla Sacco, 1892 
Turbonilla dinora Bartsch, 1912 
Proceedings of the United States National Museum, 42:265. 
Shell very elongate-conic, milk-white. Nuclear whorls small, at least 
two, about one-third immersed in the first of the succeeding turns. Post- 
nuclear whorls slightly rounded, narrowly shouldered at the summit, 
marked by very strong, very regular, broad, rounded, slightly curved, 
decidedly protractive, axial ribs, of which fourteen occur upon the first 
to seventh whorl, sixteen upon the eighth and ninth, eighteen upon the 
tenth and the penultimate turn. Intercostal spaces very strongly im¬ 
pressed, as wide as the ribs, terminating a little anterior to the suture. 
Periphery of the last whorl well-rounded; base short, well-rounded, 
marked by lines of growth and numerous, exceedingly fine spiral stna¬ 
tions; the latter also cross the ribs and intercostal spaces on the spire. 
Sutures strongly constricted. Aperture subquadrate; posterior angle ob¬ 
tuse ; outer lip thin, showing the external sculpture within; inner lip 
short, somewhat curved and revolute, without apparent fold; parietal 
wall glazed with a thin callus. Length, 9.2; diameter, 2.2 mm. (Bartsch.) 
Type in United States National Museum, No. 211553. Type locality, 
San Diego Bay, California. 
Range. Known only from type locality. 
Turbonilla buttoni Dali and Bartsch, 1909 
Bulletin 68, United States National Museum, 43; PI. 3, figs. 4, 4a. 
Shell irregularly elongate-conic, yellowish-white. Nuclear whorls 
two, very small, helicoid, having their axis at right angles to that of the 
succeeding turns, in the first of which they are very slightly immersed. 
Post-nuclear whorls slightly rounded, ornamented by very regular, 
rounded, somewhat sinuous, and decidedly protractive axial ribs, which 
extend undiminished from the summit to the periphery of the whorls 
and very feebly beyond this on the base. There are sixteen of these ribs 
upon the first to third, eighteen upon the fourth and fifth, twenty upon 
the sixth to ninth, and twenty-two upon the penultimate turn. Intercostal 
spaces well-impressed, about as wide as the ribs. Sutures well-marked, 
rendered wavy by the strong ribs. Periphery of the last whorl well- 
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