CLASS GASTROPODA 
19 
rundlich wie bei T. erosa sondern oval, und die Masse der columella 
externa beiner Arten sind ganz verschieden. (Middendorf.) 
Shell broadly elongate-conic, rather coarse, varying in color from 
white to chestnut brown. The nucleus consists of single, smooth white 
whorl, well-rounded. Post-nuclear whorls well-rounded, marked by four 
strong, somewhat flattened, spiral keels between the sutures, which are 
separated by deep, strong, spiral grooves about two-thirds as wide as the 
keels. In addition to this spiral sculpture, the whorls are marked by 
numerous fine, spiral striations and fine lines of growth. Periphery of the 
last whorl marked by a sulcus as wide as the sulci between the keels on 
the spire. Base well-rounded marked by eight equally spaced spiral cords, 
which grow successively weaker from the periphery to the umbilical area. 
In addition to these cords the base is marked by fine spiral lines and fine 
lines of growth. Aperture oval, somewhat effuse anteriorly; posterior 
angle obtuse; outer lip thin, rendered wavy by the external sculpture; 
columella short, very broad at base, somewhat twisted and reflected; 
parietal wall glazed with a thin callus. Length, 14; diameter, 5 mm. 
(Bartsch.) 
Type in Museum, St. Petersburg. Type locality, Sitka, Alaska. 
Range. Sitka, Alaska, to Puget Sound, Washington. Fossil, Fossil 
Pliocene Rock, Coos Bay, Oregon. 
Bittium eschrichtii icelum Bartsch, 1907 
Plate 77, fig. 3 
Proceedings of the United States National Museum, 33:178. 
In B. eschrichtii only the early whorls show axial ribs. In the present 
form they are well developed on all the turns, weakening only on the 
last. The type has 9 whorls (the nucleus being lost), and measures: 
length, 15; diameter, 5.5 mm. (Bartsch.) 
Type in United States National Museum, No. 15209a. Type locality, 
Neah Bay, Washington. 
Range. Straits of Juan de Fuca to Monterey, California. 
Bittium eschrichtii montereyense Bartsch, 1907 
Plate 79, fig. 5 
Proceedings of the United States National Museum, 33:178. 
This form is the southern race of B. eschrichtii. It differs from the 
typical form in being less strongly spirally keeled, much more smooth, 
more slender, and in every way more elegant than eschrichtii. The typical 
form varies in color from brown to white, and is very rarely spotted. In 
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