106 BULLETIN 68, UNITED STATES NATIONAL MUSEUM. 



on all but the last two whorls; on these the third and fourth pos- 

 terior to the periphery split into finer lines. Sutures well impressed. 

 Periphery and base of the last whorl well rounded, marked by the 

 axial ribs which extend undiminished to the umbilical area, and 

 twelve incised spiral lines, of which those immediately below the 

 periphery are the stronger. Aperture oval; posterior angle acute; 

 outer lip thin, showing the external sculpture within; columella 

 slender, slightly twisted, decidedly curved, and somewhat revolute; 

 parietal wall covered with a strong callus. 



The type and two specimens (Cat. no. 162636, U.S.N.M.) were 

 dredged at U. S. Bureau of Fisheries station 2822, off La Paz, in 21 

 fathoms, on sand bottom off Lower California. The type has ten 

 post-nuclear whorls and measures: Length 4.8 mm., diameter 1.1 mm. 



TURBONILLA (PYRGISCUS) SUBULA Morch. 

 Plate 10, fig. 3. 

 TurboniUa subula Morch, ]\Ialak. Bliltt., 1859, vol. 6, p. 120. 



Shell of medium size, white. (Nuclear whorls decollated.) Post- 

 nuclear whorls flattened in the middle, moderately contracted at the 

 suture, and slightly shouldered at the summit; ornamented by 

 strong, somewhat flexuose, narrow, and slightly retractive axial ribs, 

 of which about 16 occur upon the first of the remaining whorls, 18 

 upon the second and third, 20 upon the fourth to sixth, and 24 upon 

 the penultimate turn. Intercostal spaces about as wide as the ribs, 

 marked by nine subequal and subequally spaced incised spiral lines, 

 which pass up on the sides of the ribs, but do not cross their summits. 

 Sutures well impressed. Periphery and base of the last whorl well 

 rounded, marked by the continuations of the axial ribs, which extend 

 to the umbilicus. The base has in addition a series of spiral striations, 

 the first of which below the periphery is interrupted like those are 

 between the sutures, separated by a little greater distance from the 

 first one posterior to the periphery than that is from its neighbor 

 posterior to it ; the remaining are more or less continuous, less strong, 

 wavy, and more closely spaced. Aperture suboval; posterior angle 

 acute; outer lip thin; columella twisted and revolute; parietal wall 

 covered with a thin callus. 



The specimen described and figured is Doctor Morch's type and is 

 in the collection of the Copenhagen Museum. It was collected by 

 Dr. A. S. Oersted at Los Bocorones, a small island near Punta Arenas, 

 Costa Rica, in .30 fathoms. It has lost the early whorls; the last 

 eight only remain, which measure: Length 4.9 mm., diameter 1.3 mm. 



TURBONILLA (PYRGISCUS) WICKHAMI, new species. 

 Plate 10, fig. 9. 



Shell elongate-conic, milk-white. (Nuclear whorls decollated.) 

 Post-nuclear whorls flattened in the middle, contracted at the sutures^ 



