662 PROCEEDING.^ OF THE NATIONAL MUSEUM. vol.52. 



lip very thick, almost straight, provided with an obscure, very oblique 

 fold a little anterior to its insertion; parietal wall glazed by a thin 

 callus. 



The type Cat. No. 268634 U.S.N.M. was dredged by the U. S. 

 Bureau of Fisheries steamer Albatross at station 5678, off Redondo 

 Point, Magdalena Bay, Lower California. It has 14 postnuclear 

 whorls and measures — length, 10 mm. ; diameter, 2 mm. 



Ugartea, new subgenus. 



TurhoniUas with a fold on the parietal wall. 

 Tyi)e. — Turhonilla {Ugartea) juani Bartsch. 



TURBONILLA (UGARTEA) JUANI. new species. 



Plate 43, fig. 5. 



Shell broadly elongate conic, bluish white. Nuclear whorls at least 

 2, planorboid, having their axis almost at right angles to that of the 

 succeeding turns, in the first of which they are about half immersed. 

 Postnuclear whorls appressed at the summit with a strong sloping 

 shoulder, which extends over the posterior fourth of the space be- 

 tween the summit and the suture, the rest flattened ; marked by strong, 

 rounded, distantly spaced, almost vertical, axial ribs of which 14 

 occur upon the first and 12 upon all the remaining, excepting the 

 last, which has 14. The ribs form cusps at the anterior angle of the 

 shoulder, anterior to which they become enfeebled. Intercostal 

 spaces shallow, about 2| times as wide as the ribs, marked by closel}'' 

 spaced miscroscopic spiral striations only. Immediately behind the 

 aperture on the last turn the ribs become obsolete. Suture moder- 

 ately impressed. Periphery of the last whorl rounded. Base pro- 

 longed, marked by the continuation of the axial ribs, which become 

 evanescent before reaching the middle. Aperture narrowly oval; 

 posterior angle acute; outer lip thick within, provided with three 

 lamellar denticles on the inner surface; inner lip short, strong de- 

 cidedly revolute continuing posteriorly into the very strong parietal 

 callus, which becomes disjunct from the preceding whorl at the outer 

 edge, which renders the peritreme complete. The inner lip is pro- 

 vided with a strong oblique fold at its insertion, while the parietal 

 wall bears a short fold about halfway between this and the posterior 

 angle of the aperture. 



The type and another specimen. Cat. No. 268638, U.S.N.M., were 

 collected by the U. S. Bureau of Fisheries steamer Albatross at sta- 

 tion 5G78, off Redondo Point, Magdalena Bay, Lower California in 

 13^ fathoms on broken shell bottom. The type has seven postnuclear 

 whorls and measures — length, 4.2 mm. ; diameter, 1.3 mm. 



