Art. 11 NEW AMERICAN MARINE MOLLXJSKS — BARTSCH 11 



It has almost nine whorls remaining and measures, length, 11.6 mm., 

 diameter, 2.8 mm. 



TURBONILLA (MORMULA) CLEMENTINA, new speeies 



Plate 2, figs. 9, 10 



Shell broadly elongate-conic, chestnut brown. Nuclear whorls a 

 little more than two, forming a depressed helicoid spire, the axis of 

 which is at right angles to that of the succeeding turns, in the first 

 of which the nuclear spire is about one-fifth immersed. The nuclear 

 whorls project slightly beyond the left outline of the postnuclear 

 spire. First postnuclear whorl well rounded, the succeeding five 

 somewhat shouldered, about one-third the distance between the 

 summit and the suture, anterior to the summit, while the last three 

 are slighly rounded and rendered slightly concave below the some- 

 what excurved summit. The whorls are marked by slightly protrac- 

 tive axial ribs, which are strong on the early whorls and become 

 enfeebled on the later turns. Of these ribs, 24 occur upon the first, 

 20 upon the second, 18 upon the third, 20 upon the fourth and fifth, 

 24 upon the sixth, 26 upon the seventh, 30 upon the eighth, and 34 

 upon the last turn. The spaces which separate these ribs are a little 

 narrower than the ribs on the early turns, and about equal to the 

 ribs on the last turn. In addition to the axial ribs the whorls are 

 marked by six strong, incised spiral lines, which almost equally 

 divide the posterior three-fourths of the whorls. The space between 

 the summit and the first strongly incised pit is marked by five fine 

 incised spiral lines, while the space between the fourth and fifth pit 

 is also divided by a fine spiral line, which is a little nearer the fourth 

 pit than the fifth. Sutures rendered rather conspicuous by the very 

 narrowly shouldered summit of the whorls. Periphery of the last 

 turn well rounded. Base short, well rounded, marked by 15 incised 

 spiral lines, which gradually diminish in spacing and strength from 

 the periphery to the umbilicus. The six at the umbilical region are 

 very fine and very closely crowded. The rest increase regularly in 

 size and spacing, excepting the fourth anterior to the periphery, 

 which is much finer than the third and fifth. Aperture subquadrate ; 

 posterior angle obtuse; outer lip thin; inner lip almost vertical, 

 reflected over and appressed posteriorly for about one-third of its 

 distance to the base ; parietal wall covered by a thin callus. 



The type. Cat. No. 340933, U.S.N.M., comes from San Clemente 

 Island, California. It has nine and a half whorls and measures 

 length, 7.6 mm,; diameter, 2.3 mm. This species is nearest related 

 to TurhonUla {Pyrgolampros) dora Bartsch. 



