WEST AMERICAN PYRAMIDELLID MOLLUSKS. 195 



ODOSTOMIA (EVALEA) KILLISNOOENSIS, new species. 

 Plate 22, fig. 7. 



Shell very elongate ovate, umbilicated, yellowish white. Nuclear 

 whorls very small, obliquely, almost completely immersetl in the first 

 of the succeeding turns. Post-nuclear whorls evenly, moderately 

 rounded, with very faintly shouldered summits, marked by numerous, 

 fairly strong, equal and equally closely spaced, w^avy, spiral stria- 

 tions, and fine retractive lines of growth. Peripher}' and base of last 

 whorl well rounded, marked like the spire. Suture well impressed. 

 Aperture ovate, somewhat effuse anteriorly, posterior angle acute; 

 outer lip thin; columella very oblique, posterior two-thirds straight, 

 and strongly reflected, anterior third strongly curved; columellar 

 fold strong, oblique, situated at the insertion of the columella; 

 parietal wall covered by a thin callus. 



The type (Cat. no. 159457, U.S.N.M.) was coUected by A. Krause, 

 at Killisnoo, Alaska. It has six post-nuclear whorls and measures: 

 Length 6.4 mm., diameter 3 mm. Three other specimens (Cat. no. 

 205214, U.S.N.M.) from the same place by the same collector were 

 donated to the U. S. National Museum by the Berlin Museum, in 

 whose collection three additional specimens are listed under Cat. no. 

 36334. 



ODOSTOMIA (EVALEA) TILLAMOOKENSIS Dall and Bartsch. 



Plate 22, lig. 2. 



Odostomia (Evalea) tillamookcnsis Dall and BARTSfH, Proc. U. S. Nat. Mus., 

 vol. 33, 1907, pp. 522, 523, pi. 47, fig. 1. 



Shell elongate-conic, thin, yellowish white. Nuclear whorls sur- 

 rounded by the first of the succeeding turns and so immersed as to 

 give the apex a broadly truncated appearance. Post-nuclear whorls 

 inflated, evenly strongly rounded, very slightly shouldered at the 

 summit, separated b}^ well-marked sutures. Periphery and base of 

 the last whorl well rounded, the latter inflated, narrowly openly 

 umbilicated. Entire surface marked b}^ numerous fine, wa\^', sub- 

 equal, weakly incised spiral lines, of which about 35 occur between 

 the summit and the periphery of the last whorl and about an equal 

 number on the base. Aperture oval; outer lip thin; columella slen- 

 der, evenly gently curved, and slightly revolute, free, not reenforced 

 at the base, provided with a slender fold at its insertion, which is not 

 visible when the aperture is viewed square h'. 



The type (Cat. no. 196244, U.S.N.M.) has four post-nuclear whorls 

 and measures: Length 4.1 mm., diameter 2.2 mm. It was dredged 

 by the U. S. Bureau of Fisheries steamer Albatross at station 3346, off 

 Tillamook. Oregon, in 786 fathoms, green mud, bottom tempera- 

 ture 37°.3. 



