4 PROCEEDINGS OF THE NATIONAL MUSEUM vol.69 



TUEBONILLA (CHEMNITZIA) RIMACA, new species 



Plate 1, fig. 7 



Shell small, elongate-conic, semitransliicent, bluish-white. Nuclear 

 whorls 11/2, strongly rounded, smooth, forming a depressed helicoid 

 spire, the axis of which is almost at right angles to that of the suc- 

 ceeding turns, in the first of which almost half of the nuclear spire 

 is immersed. Postnuclear whorls moderately rounded, appressed at 

 the summit, somewhat obscurely angulated at the termination of the 

 anterior third between summit and suture, marked by low, rounded, 

 distantly spaced, almost vertical axial ribs, of which 12 occur upon 

 the first four turns, and 14 upon the rest. The spaces between the 

 axial riblets are shallow, only moderately impressed, and almost 

 three times as wide as the ribs. Suture well marked. Periphery of 

 the last whorl strongly rounded. Base rather long, well rounded, 

 marked only b}^ incremental lines. Aperture oval, very elongated; 

 outer lip thin, showing the external sculpture within, inner lip 

 strongly twisted, bearing a heavy fold at its insertion. 



The type (Cat. No. 363068, U.S.N.M.) has six postnuclear whorls 

 and measures, length, 3.2 mm. ; diameter, 0.8 mm. 



TURBONILLA (STRIOTURBONILLA) HUA, new species 



Plate 1, fig. 5 



Shell very irregularly elongate-conic, bluish-white, semitranslu- 

 cent. Nuclear whorls 2.3, strongly rounded, forming a decidedly 

 elevated spire, the axis of which is at right angles to that of the 

 succeeding turns, in the first of which the nuclear spire is about one- 

 third immersed. Postnuclear whorls narrowly shouldered at the 

 summit, moderately rounded, crossed by rather strong, obliquely, 

 protractively slanting axial ribs which are a little more than one- 

 half as wide as the spaces that separate them. Of these ribs, 16 

 occur upon the second, 18 upon the third, 20 upon the fourth and 

 fifth, and 22 upon the rest of the whorls. The axial ribs terminate 

 rather strongly at the summit, and there appears to be a slight con- 

 striction immediately below the summit, which gives to the angle at 

 the summit a somewhat crenulated aspect. The intercostal spaces 

 terminate abruptly at the periphery, and are crossed by numerous 

 microscopic spiral striations. Suture rendered conspicuous by the 

 shoulder at the summit. Periphery well rounded. Base short, well- 

 rounded, marked by incremental lines only. Aperture subquadrate; 

 posterior angle obtuse ; outer lip thin, shoAving the external sculpture 

 within ; inner lip almost vertical, slightly twisted, and provided with 

 an oblique fold at its insertion. 



