WEST AMERICAN PYRAMIDELLID MOLLUSKS. 107 



with a moderately broad, sloi)ing shoulder at the siiinniit marked by 

 well-developed, rounded, very regular, slightly protractive axial ribs, 

 of which 20 occur upon the second and 22 upon the remaining, except- 

 ing the penultimate whorl, which has 32. Intercostal spaces a little 

 wider than the ribs, marked by seven series of spiral pits, of which 

 the third below the summit is almost twice as wide as the rest. 

 Sutures moderately constricted. Periphery of the last whorl well 

 rounded. Base short, well rounded, marked by the continuations of 

 the axial ribs, which extend to the umbilical area, and 11 incised 

 spiral lines, of which those immediately below the periphery are some- 

 what interrupted and wider than the rest. Aperture rhomboidal; 

 posterior angle acute; columella rather stout, revolute. 



The tv^pe (Cat. no. 206879, U.S.N.M.) and three specimens were 

 dredged by the University of California at station 32, off Santa Cata- 

 lina Island, California. It has 10 post-nuclsar whorls and measures: 

 Length 8 mm., diameter, 2.1 mm. 



Named for Prof. H. F. Wickham. 



TURBONILLA (PYRGISCUS) LARA, new species. 

 Plate 10, figs. 6, 6«, 66. 



Shell small, slender, milk-white. Nuclear whorls two and one- 

 fourth, forming a depressed, helicoid spire, having its axis at right 

 angles to that of the succeeding turns, in the first of which it is very 

 slightly immersed. Post-nuclear whorls flattened in the middle, 

 rounding slightly toward the moderatel}^ shouldered simimit, some- 

 what contracted at the suture, marked by fairly strong, straight, 

 slightly retractive axial ribs, of which 18 occur upon the first and 

 second and 20 upon all the remaining whorls excepting the penulti- 

 mate turn, which has 22, Intercostal spaces varving from one and 

 one-half to two times the width of the ribs, marked b}^ nine series of 

 spiral pits, of which the j^eripheral and the fifth above the periphery 

 are the widest; the third and fourth above the periphery and the two 

 immetliateW below the summit, are a little narrower than the rest. 

 The segments left between the pits form almost equal raised cords. 

 Sutures well marked. Periphery of the last whorl and base moder- 

 ately well rounded, ornamented by the continuations of the axial ribs 

 and three strong, interrupted lines of pits on the posterior half and 

 five slender lines on the anterior. Aperture oval; posterior angle 

 acute; outer lip thin, showing the external sculpture within; columella 

 slender, curved, and slightly revolute. Parietal wall covered by a 

 thin callus. 



The type (Cat. no. 96707, U.S.N.M.) and sixty-six specimens were 

 dredged at U. S. Bureau of Fisheries station 2823, off La Paz, in 

 27 fathoms. It has nine jDost-nuclear whorls and measures : Length 

 4.3 mm., diameter 2 mm. 



