178 



BULLETIN 68, UNITED STATES NATIONAL MUSEUM. 



strong spiral lamella^, the first of wliich renders tlie summit of the 

 whorls decidedly tabulated, while the second one is situated a little 

 posterior to the posterior termination of the anterior third between 

 the sutures. Both lamellae are faintly nodulous; the posterior one 

 slightly more so than the anterior. The deep channel between the 

 two keels is marked by very feeble slender axial threads. Periphery 

 of the last whorl marked b}^ a lamella a little less strong than those 

 between the sutures. Base with two lamellae, the anterior of which is 

 immediately behind the columella and much less developed than the 

 median one, wliich is somewhat weaker than the peripheral lamella. 

 The depressed spaces between these lamellae are crossed by axial 

 threads, as on the spire. Aperture irregularly ovate; posterior angle 

 decidedly obtuse; outer lip rendered angular by the spiral lamellae; 

 columella strong, somewhat twisted, reenforced by the base. 



The type, which is at Amherst College, was collected by Professor 

 C. B. Adams in Panama Bay. It has five post-nuclear whorls and 

 measures: Length 2.2 mm., diameter 1 mm. 



ODOSTOMIA (MIRALDA) JEPYNOTA, new species. 

 Plate 19, fig. 5. 



Shell pupiform, translucent. Nuclear whorls small, obliquely im- 

 mersed in the first post-nuclear turns, marked by four spiral cords. 

 Post-nuclear whorls with the summits appressed, marked by two 

 strong, spiral keels between the sutures, a tliird at the periphery, 

 and a fourth on the middle of the base, the last two somewhat less 

 strong than the rest. The posterior keel forms the strong tabula- 

 tion at the summit of the whorls and is strongly tuberculated, 14 

 tubercles appearing upon the second and 20 upon the remaining 

 whorls. The space between the keels is marked b}" rather strong 

 lines of growth. The greatest convexity coincides with the super- 

 peripheral keel. Aperture irregularly ovate, somewhat effuse ante- 

 riorly; posterior angle obtuse; outer lip angulated by the keels, 

 thin, showing the external markings within; columella strong, cui"ved, 

 without visible fold in the aperture; reenforced b>'^ the base; parietal 

 wall covered by a thin callus. 



The type and 30 specimens (Cat. no. 129335, U.S.N.M.) comes from 

 San Pedro. The type has five post-nuclear whorls and measures: 

 Length 1.9 mm., diameter 0.9 mm. 



Examination of the following specimens has been made: 



U.S.N.M. 

 cat. no. 



129335 

 105467 

 16222 



No. of 

 spec'i- 



Localily. 



San Pedro, California 



San Diego, California 



Cape St. Lucas, Lower California 



San Pedro, California 



Whites Point, California 



Catalina Island, California 



Disposition of 

 material. 



U. S. Nat. Mus. 



Do. 



Do. 

 Oldroyd coll. 



Do. 

 S. S. Berry coll. 



