WEST AMERICAN PYRAMIDELLID MOLLUSKS. 49 



little more so on the shoulder than on the summit, which gives them 

 a contractetl appearance at this place, terminating a little above the 

 suture. Sutures well impressed. Entire surface of base and si)ire 

 marked by fine, wavy, spiral striations. Periphery and the moderately 

 long base of the last whorl well rounded. Aperture rhoinboidal; 

 outer lip thin, showing the external sculj)ture within: columella mod- 

 erately strong, slightly curved. 



The two cotypes and four additional s})ecimens (Cat. no. 162442, 

 U.S.N.M.) were dredged by the U. S. Bureau of Fisheries, at station 

 2823, in 26^ fathoms off La Paz, Lower California. One of the 

 cotypes has the nucleus and nine post-nuclear whorls, and measures: 

 Length 3.1 mm., diameter 0.9 mm. The other cotype consists of the 

 last seven post-nuclear whorls; if perfect, it would probably have 

 had twelve. This measures: Length 3.6 mm., diameter L2 mm. 



Named for Prof. Samuel Calvin. 



TURBONILLA ( STRIOTURBONILLA) CARPENTERI, new species. 



Plate 3, fig.s. 9, 9a. 



Shell long, slender, bluish-white. Nuclear whorls small, two and 

 one-half depressed, helicoid, having their axis at right angles to that 

 of the succeeding turns, in the first of which they are about one-fifth 

 immersed . Post-nuclear whorls exceedingly high })etween the sutures, 

 evenly rounded, marked by almost vertical axial ribs, which become 

 slightly expanded and flattened at the summits. There are 18 of 

 these ribs upon the first to third, 20 upon the fourth to sixth, 22 upon 

 the seventh, 24 upon the eighth and ninth, and 26 upon the tenth. 

 Upon the penultimate turn they become tlecidedly irregular and en- 

 feebletl. Intercostal spaces about one-half as wide as the ribs, but 

 little depressed below the general surface of the shell. Sutures some- 

 what constricted. ' Periphery of the last whorl well rounded. Base 

 short and somewhat inflated, marked by feeble extensions of the axial 

 ribs. Entire surface of spii-e and base crossed by numerous fine, 

 wavy, s})iral striations. Aperture sulK|uadrate, rather elongated, 

 posterior angle obtuse, outer li}) thin; columella rather long, slender, 

 slightly sinuous. 



The type (Cat. no. 160065, U.S.N.M.) has twelve post-nuclear 

 whorls, and measures: Length 7.9 mm., diameter 1.7 mm., and w:js 

 collected at San Pedro, California. Two specimens from the same 

 locality were identified for Mrs. Oldroyd. 



Named for Doctor P. P. (\iipenter. 



TURBONILLA (STRIOTURBONILLA) SIMPSONI, new species. 

 Plate ;^, figt*. (), ()(/. 



Shell elongate-conic, rather slender, bluish-white. Nuclear whorls 

 two and three-fourths, depressed, helicoid, having their axis at right 

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



