NO. 2193. WEST AMERICAN MARINE M0LLU8K8—BARTSCH. 659 



oval; posterior angle obtuse; outer lip thin, showing the external 

 sculpture within; inner lip stout, slightly curved and somewhat 

 revolute, provided with a moderately strong oblique fold a little an- 

 terior to its insertion. Parietal wall covered with a thin callus. 



The type, Cat. No. 267744«, U.S.N.M., was collected in shallow 

 water in Santa Maria Bay, Lower California. It has nine post- 

 nuclear whorls and measures — length, 4.8 mm. ; diameter, 1.4 mm. 



TURBONILLA (PYRGISCUS) ULLOA, new species. 

 Plate 43, fig. 4. 



Shell elongate conic, yellowish white. Nuclear whorls and all but 

 the last 5| postnuclear turns decollated. The whorls remaining are 

 flattened, almost appressed at the summit, marked b}' 18 quite regular, 

 slightly protractivel}^ slanting, well-rounded axial ribs. Intercostal 

 spaces shallov>', about two times as wide as the ribs, crossed by eight 

 incised spiral grooves, of which the second, third, seventh, and eighth 

 are of equal width and much stronger than the rest; the remaining 

 four are also of equal width, but only about one-fourth as wide as the 

 rest. The spaces between the first and second and second and third 

 are equal and almost doubly as wide as those between the summit and 

 the first, the third and fourth, and sixth and seventh ; the space be- 

 tween the seventh and eighth is a trifle narrower than the last men- 

 tioned, and those between the fourth and fifth and fifth and sixth 

 are a little less wide than this. Suture moderately constricted. 

 Periphery of the last whorl well rounded. Base moderately long, 

 well rounded, marked by the feeble continuations of the axial ribs, 

 which become evanescent before reaching the middle of the base, 

 and 11 strongly incised subequally spaced lines. These is a broad 

 smooth band below the periphery equal to the space between the first 

 and second incised line on the spire of the last whorl. Aperture 

 broadly oval, posterior angle acute; outer lip thin, showing the ex- 

 ternal sculpture within ; inner lip slender, very oblique, and decidedly 

 revolute, provided with a moderately strong fold immediately below^ 

 the insertion ; parietal wall covered by a thick callus. 



The type. Cat. No. 267744e, U.S.N.M., was dredged in shallow 

 water in Santa Maria Bay, Lower California. It consists of a little 

 more than the last five whorls and measures — length, 4 mm. ; diam- 

 eter, 1.2 mm. 



TURBONILLA (PYRGISCUS) CABRILLOI. new species. 



Plate 45, fig. 3. 



Shell broadly elongate conic, pale yellow horn colored. Nuclear 



whorls 2^, well rounded, forming a decidedly depressed helicoid spire 



having its axis at right angles to that of the succeeding whorls, in 



the first of which, the tilted edge is about one-fourth immersed. 



