354 PROCEEDISaS OF THE NATIOXAL .UUSEUM. vol. xxx. 



these ribs occur upon the first, twenty upon the third, twent^^-two upon 

 the fifth, and twentj^-six upon the penultimate whorl. Intercostal 

 spaces, about as wide as the ribs, crossed by well-incised, equal and 

 subequally spaced spiral lines which are about one-fourth as wide as 

 the spaces inclosed between them. There are no spiral lines in the 

 intercostal spaces near the summit of the whorls; the first one falls 

 about parallel with the anterior limit of tlie cuspid summit of the axial 

 ribs; nine lines occur between the sutures on the fourth, eleven on the 

 fifth, and twelve on the penultimate whorl. Periphery of the last whorl 

 verv slightly angulated. Base well rounded, marked by strong- con- 

 tinuations of the axial ribs, which extend to the umbilical region, and 

 eighteen incised spiral lines in the intercostal spaces; these lines grad- 

 ually become more crowded toward the uml)ilical region. Aperture 

 moderately large, suboval, somewhat effuse at the junction of the outer 

 lip and coliunclla; posterior angle acute, outer lip thin, showing the 

 external sculpture within; columella oblique, slightly curved, and 

 somewhat revolute, reenforced by the somewhat attenuated basal por- 

 tion of the last whorl; ]:)rovided with a weak oljlique fold at its inser- 

 tion; parietal wall without perceptible callus. 



The specimen described and figured is Garrett's type. It belongs to 

 the Philadelphia Academy of Natural Sciences, where it is entered as 

 No. 581<)t>. It comes from the Yiti Islands, has seven post-nuclear 

 whorls and measures: long. 3 mm.; diam. 1.1 nun. The Pietel col- 

 lection contains a specimen which was collected at Upolu, one of the 

 Samoan Islands. 



EG I LIN A, new subgenus. 



Odostomias having strong axial ribs between the sutures which are 

 interrupted at the periphery by a deep spiral sulcus. Intercostal 

 spaces smooth. Base ornamented ])y spiral keels, the spaces between 

 which are marked b}' many ver}^ slender axial threads. 



T(/pe. — Odostomia {Egilina) niarieUa A. Adams. 



ODOSTOMIA (EGILINA) MARIELLA A. Adams, 

 riate XXII, tig. 4. 

 Parihmia marieUa A. Adams, Ann. Mag. Nat. Hist., VI. lS(iO, \\. 415. 



Shell small, umbilicated, regularly conic with ol)liquely truncated 

 apex and deeply channeled sutures; milk-white. Nuclear whorls 

 almost completely immersed in the first post-nuclear whorl; only half 

 of the last volution projects above it. Post- nuclear whorls flattened, 

 marked b}' strong, very obliquely backward-slanting axial ribs, which 

 are thickened at the sunnnits and constricted a little below the sum- 

 rait, which renders the top of each rib beaded. Anteriorl}^ the ribs 

 are terminated by the posterior margin of the peripheral sulcus; here 

 the ribs expand somewhat and almost fuse, and this expansion gives 



