10 PKOCEEDINGS OF THE NATIONAL MUSEUM vol.60 



strongly rounded with mere indications of axial ribs; the second one 

 also strongly rounded with 14 low, rounded, distantly spaced axial 

 ribs; the third and fourth turn are also well rounded and marked 

 with the same number of ribs, while the remaining turns are almost 

 flattened and each marked by 14 very strongly retractively slanting, 

 curved axial ribs. Intercostal spaces broad but lightly impressed, 

 marked by 21 incised spiral lines which become progressively a little 

 wider spaced from the summit to the periphery. Suture well im- 

 pressed. Periphery of the last whorl with a series of very strongly 

 impressed spiral pits. Base well rounded, marked by numerous 

 closely spaced spiral striations. Aperture rather large, oval; pos- 

 terior angle acute; outer lip thin, showing the external sculpture 

 within; inner lip somewhat twisted, reflected over and appressed to 

 the base for about half its length ; parietal wall covered by a thick 

 callus. 



The type (Cat. Xo. 3(33081, U.S.N.M.) has seven postnuclear whorls 

 and measures, length 3.3 mm.; diameter, 1 mm. 



Cat. No. 363082, U.S.N.INI. contains three additional specimens. 



TURBONILLA (PYRGISCUS) RIMA, new species 



Plate 2. fig. 7 



Shell elongate-conic. Nucleus and early postnuclear whorls flesh- 

 colored, the rest yellowish-horn colored. Nuclear whorls 2i/2? well 

 rounded, forming a large helicoid apex, the axis of which is at right 

 angles to that of the succeeding turns, in the first of which it is 

 scarcely at all immersed; the tilted edge of the nucleus projects 

 slightly beyond the outline of the postnuclear spire on both sides. 

 Postnuclear whorls decidedly high between the summit and the pe- 

 riphery ; the first one very high and well rounded, the second and third 

 becoming progressively less rounded, while the rest are flattened. 

 The first postnuclear turn is almost smooth, having scarcely any indi- 

 cation of axial ribs, these being reduced to a few obsolete retrac- 

 tively slanting lines. The second one has poorly developed ribs 

 which are here, as well as on the other whorls to follow, decidedly 

 retractively slanting. There are 26 of them on the second whorl, and 

 from there on the ribs become strong and well rounded, and about 

 as wide as the spaces that separate them. The third whorl has 20, 

 the fourth 22, the fifth 26, and the last 28. The intercostal spaces 

 are rather shallow and are crossed by six broad incised spiral lines 

 which are of almost equal width and spacing. Suture rendered 

 slightly sinuous by the ribs at the summit. Periphery of the last 

 whorl well rounded. Base short, well rounded, marked by the feeble 

 continuations of tlie axial ribs, which become evanescent before reach- 



