ART. 20 ADDITIONAL MOLLUSKS FROM ECUADOE BARTSCH 5 



The type (Cat. No. 363069, U.S.N.M.) is not quite adult. It has 

 seven postnuclear whorls and measures, length, 3 mm.; diameter, 

 0.8 mm. 



TURBONILLA (STRIOTURBONILLA) ATA. new species 



Plate 1, fig. 8 



Shell very irregularly elongate-conic, pale brown. Nuclear whorls 

 2.3, well rounded, forming a depressed helicoid spire whose axis is 

 almost at right angles to that of the succeeding turns, in the first of 

 which it is about one-fourth immersed. The left edge of the nuclear 

 spire projects beyond the outline of the postnuclear spire. Early 

 postnuclear whorls moderately rounded, the later ones almost flat- 

 tened; the early whorls are somewhat worn in our specimen, and 

 consequently no rib count can be made. The later turns are slightly 

 shouldered at the summit and crossed by slender, almost straight 

 protractively slanting axial ribs of which 20 occur upon the fourth, 

 22 upon the fifth, 20 upon the sixth to ninth, and 22 upon the last 

 whorl. The spaces separating the axial ribs are about as wide as 

 the ribs and are crossed by a deeply impressed line of pits which is 

 situated about two-fifths of the space between the summit and the 

 suture anterior to the summit. A second line of pits of about equal 

 width, but a little more profoundly impressed, marks the anterior 

 termination of the intercostal spaces. In addition to these two lines 

 of pits, the rest of the intercostal spaces are marked by numerous 

 very fine, closely spaced spiral striations. Suture well impressed. 

 Periphery of the last whorl slightly angulated. Base short, marked 

 by numerous slender closely spaced spiral threads. Aperture elon- 

 gate-ovate ; posterior angle acute ; outer lip thin, showing the exter- 

 nal sculpture within; inner lip almost straight, provided with a 

 moderately strong fold a little anterior to its insertion. 



The type (Cat. No. 363070, U.S.N.M.) has lOi/s whorls and meas- 

 ures, length, 6.3 mm. ; diameter, 1.4 mm. 



TURBONILLA (STRIOTURBONILLA) CACA, rew species 



Plate 1, fig. 9 



Shell elongate-conic, turreted, bluish-white. Nuclear whorls 21^, 

 well rounded, forming a decidedly elevated spire whose axis is at 

 right angles to that of the succeeding turns, in the first of which the 

 TUiclear spire is about one- fourth immersed. Postnuclear whorls 

 stronglj' tabulatedly shouldered at the summit, the rest only slightly 

 rounded, marked by strong retractivel}^ slanting axial ribs, of which 

 18 occur upon the first, 20 upon the second to sixth, 22 upon the 

 seventh, and 24 upon the last turn. The intercostal spaces are about 

 as wide as the ribs, the impressed portion terminating abruptly at the 



