WEST AMERICAN PYRAMIDELLTD MOLLUSKS. 95 



TURBONILLA (PYRGISCUS) CANFIELDI Dall and Bartsch. 



Plate 9, figs. 3, 3a. 



TurboniUa (Pyrgiscus) canfieldi Dall and Bartsch, Proc. U. S. Nat. Mus., vol. 

 33, 1907, pp. 504, 505, pi. 47, figs. 4, 4a. 



Shell slender, elongate-conic, with the posterior half of the exposed 

 portion of the whorls on the spire white and the anterior half chest- 

 nut brown, base white. Nuclear whorls two and two-thirds, large, 

 smooth, forming a depressed helicoid spire whose axis is at right 

 angles to the axis of the succeeding turn; not immersed and extend- 

 ing slightly beyond the outline of the spire on both sides. Post- 

 nuclear whorls very slightly rounded, weakly roundly shouldered at 

 the summit and very moderately contracted at the periphery, orna- 

 mented by very strong, broad, low, rounded, almost vertical axial 

 ribs of which there are 22 upon the first, 24 upon the antepenultimate, 

 and 28 upon the penultimate turn. These ribs extend prominently 

 to the summit and crenulate the subchanneled sutures. Intercostal 

 spaces narrow, not more than half the width of the ribs, crossed by 1 9 

 incised spiral lines which are of almost equal width and subequally 

 spaced with the following exceptions, the seventh, eleventh, and the 

 last three above the periphery are much wider, appearing as quad- 

 rangular pits in the intercostal spaces, the eleventh falling on about 

 the middle of the exposed portion of the whorl on the spire, and the 

 seventh about halfway between this and the summit. Periphery and 

 base of the last whorl well rounded, the latter marked by the feeble 

 continuations of the axial ribs which gradually disappear after cross- 

 ing the periphery, and about 16 subequally spaced incised spiral lines. 

 Aperture oval, somewhat effuse anteriorly, columella oblique, some- 

 what twisted, with a weak oblique fold a little anterior to its insertion. 



The type (Cat. no. 196229, U.S.N.M.) was dredged by Mr. S. S. 

 Berry in 12 fathoms off Del Monte, Monterey, California. It has 10 

 post-nuclear whorls and measures: Length 6.3 mm., diameter 1.2 mm. 



TURBONILLA (PYRGISCUS) ALMO, new species. 

 Plate 9, figs. 8, 8a. 



Shell slender, light brown, wax-yellow at tip. Nuclear whorls 

 very small, two and one-half, planorboid, having their axis at right 

 angles to that of the succeeding turns, in the first of which they are 

 slightly immersed. First post-nuclear whorl almost smooth, the sec- 

 ond with a mere indication of ribs, well rounded. The remaining 

 post-nuclear whorls somewhat overhanging, appressed at the sum- 

 mit, well rounded, marked by moderately developed, rounded, 

 retractive axial ribs, of which about 20 occur upon all but the penulti- 

 mate whorl; upon this there are 22. Intercostal spaces a little wider 



