12 PROCEEDINGS OF THE NATIONAL. MUSEUM Vol.70 



ODOSTOMIA (SALASSIA) GENOA, new species 



Plate 2, fig. 3 



Shell rather large, conic, grayish white. Nuclear whorls decol- 

 lated. Postnuclear whorls rather high between the summit and the 

 periphery, slopingly shouldered at the summit, marked by 24 some- 

 what retractively slanting, axial riblets which are separated by 

 shallow intercostal spaces, the latter being a little narrower than 

 the riblets. These riblets extend from the summit to the periphery 

 while from the periphery basally they gradually evanesce. Suture 

 rather strongly constricted. Base moderately long, well rounded. 

 Aperture oval; posterior angle obtuse; columella provided with a 

 strong oblique fold which is situated a little anterior to the inser- 

 tion of the columella ; parietal wall covered by a rather thick callus. 



The type, Cat. No. 362441, U.S.N.M., was collected by Dr. K. H. 

 Tremper in 6 fathoms off Dead Mans Island, San Pedro, California. 

 It has almost seven whorls and measures, length 7 mm., diameter, 

 2.1 mm. 



ODOSTOMIA (CHRYSALLIDA) FIA, new species 



Plate 3, fig. 8 



Shell elongate-ovate, cream-yellow. Nuclear whorls deeply im- 

 mersed in the first of the postnuclear turns above which the tilted 

 edge of the last volution only projects. Postnuclear whorls strongly 

 shouldered at the summit, and decidedly constricted at the suture, 

 moderately rounded, marked by three strongly tuberculated spiral 

 ridges and a fourth smooth one between the summit and the suture. 

 These ridges are crossed by strong, somewhat retractively slanting 

 axial ribs, of which 18 occur upon the second, 20 upon the third, and 

 18 upon the penultimate turn. The junction of the spiral cords and 

 axial ribs form strong nodules which are almost hemispherical, while 

 the spaces inclosed between them form deep rounded pits. The 

 space between the third and the fourth, or smooth spiral cord, is 

 crossed by fine threadlike axial riblets. Suture deeply channeled. 

 Periphery of the last whorl strongly rounded. Base rather long, 

 well rounded, marked by six strong slightly flattened spiral cords 

 which grow successively weaker from the periphery toward the tip 

 of the base. The spaces separating these cords also grow consecu- 

 tively a little less in width, and are crossed by numerous fine thread- 

 like axial riblets. Aperture rather large, effuse anteriorly; posterior 

 angle obtuse; outer lip rendered sinuous by the external sculpture; 

 inner lip reflected and appressed to the base for almost its entire 

 length, provided with a moderately strong fold at its insertion; 

 parietal wall covered with a thin callus. 



