26 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 65 



which extend to the umbilical chink. Aperture rather large, broadly 

 oval; posterior angle obtuse; outer lip thin; inner lip slightly curved 

 and reflected, with the posterior third reflected over and appressed to 

 the base. There is an oblique feeble fold on the columella a little 

 anterior to its insertion. 



Type.— C?it. No. 333507, U.S.N.M., has lost the nucleus and fii-st 

 two postnuclear turns. The 9.5 whorls remaining measure : Length, 

 12 mm. ; diameter, 3.3 mm. 



The nucleus and the first two postnuclear turns were described 

 from a young specimen, Cat. No. 352507, U.S.N.M., having nine post- 

 nuclear whorls, which measures: Length, 7.1 mm.; diameter, 2.2 mm. 



Twenty-seven additional specimens are in the Oldroyd collection. 



This species belongs near Turbonilla {Pyrgolampros) hannibali, 

 Bartsch. 



TURBONILLA (PYRGOLAMPROS) IDAE. new species. 



Plate 1, fig. 9. 



Shell of medium size, elongate conic, pale brown. Nuclear 

 whorls two and a half, forming a very small, slightly elevated heli- 

 coid spiral, the axis of which is at right angles to that of the suc- 

 ceeding turns, in the first of which the tilted edge of the nuclear 

 spiral is about one-fourth immersed. The first two or three post- 

 nuclear whorls well rounded, the succeeding turns almost flattened, 

 or sometimes evenly slightly concave. All the whorls very nar- 

 rowly shouldered at the summit. The first postnuclear whorl 

 smooth, the second one showing mere indications of axial riblets, 

 while on the succeeding turns they become increasingly stronger, 

 well rounded, and somewhat protractively slanting. Of these riblets, 

 20 occur upon the third, 18 upon the fourth to sixth, 20 upon the 

 seventh, 22 upon the eighth, 24 upon the ninth, and 34 upon the 

 last turn. On this they become less conspicuous. Intercostal spaces 

 mere lines on the first turns, while on the median whorls they are 

 about half as wide as the axial ribs, and on the last turn they are 

 again materially reduced. Suture slightly constricted. Periphery 

 of the last whorl somewhat inflated, well rounded. Base short, 

 somewhat inflated, well rounded, marked by the feeble continuations 

 of the axial riblets, which extend to the umbilical chink. The entire 

 surface of the spire and base crossed by numerous, closely spaced 

 spiral striations. Aperture broadly oval; posterior angle acute; 

 outer lip thin; inner lip curved, rather strongly reflected, almost 

 free throughout its entire length, posteriorly covering the greater 

 portion of the umbilical chink. A feeble twist is present on the 

 columella at its insertion. 



