Doll — Neic Species of Shells from Lower California. 7 



? Trichotropis (Provanna) lomana, new species. 



Shell thin, white under a dull smooth olive-green periostracum, decol- 

 late but indicating more than three whorls; suture deep but not chan- 

 nelled, whorls well rounded; axial sculpture on the last whorl of about 

 twenty slightly arcuate ribs, with subequal interspaces, ceasing abruptly 

 at the periphery; on the preceding whorls these extend from suture to 

 suture; on the base the axial sculpture is reduced to inconspicuous incre- 

 mental lines; spiral sculpture, behind the periphery, of obscure close-set 

 threads only visible in the interspaces; in front of the periphery and be- 

 tween it and the canal are four or five strong cords with narrower deep 

 interspaces, slightly crenulating the thin anterior margin of the outer lip; 

 aperture rounded, throat white, showing the impress of the external 

 sculpture; body and inner lip with a thin white layer of callus; pillar 

 arcuate, angulate at the extremity; canal very short and rather wide. 

 Length of (decollate) two and a half whorls, 7.0; of last whorl, 6.0; of 

 aperture, 4.0; max. diameter, 5.5 mm. 



Habitat. — Off Point Loma, San Diego Co., Cal., at station 4354, U. S. 

 Bureau of Fisheries in 650 fathoms, mud, bottom temperature, 38° 5 F. 

 U. S. Nat. Mus. Cat. No. 209112. 



This species wants the fimbriate periostracum of Trichotropis and the 

 canal is more rounded than in the shallow water species of the genus, 

 but in the absence of soft parts and operculum the shell seems nearer to 

 that group than to any other. The type of sculpture recalls that of some 

 Rissoidae and some species of Chrysallida. 



Liotia ratnmata, new species. 



Shell depressed-turbinate, of four whorls, the first two and two-thirds 

 whorls and the base of the last whorl white, the upper surface of the last 

 whorl and one-third reddish purple; the suture distinct, not appressed; 

 spiral sculpture on the spire of two prominent threads, the posterior 

 angulating the shoulder, the anterior growing more feeble on the last 

 whorl; the rest of the surface is uniformly covered with fine equal close- 

 set smaller threads slightly roughened by fine incremental lines; the 

 only axial sculpture consists of feeble more or less obsolete plications in 

 front of the suture; base rounded, with a small perforate umbilicus of 

 which the margin is notcrenate; aperture circular thickened below. 

 Breadth of shell, 4.7; height, 4.0 mm. 



Habitat.— Magdalena Bay, L. Cal., C. R. Orcutt. U. S. Nat. Mus. 

 Cat. No. 217,908. 



Liotia olivacea, new species. 



Shell of five depressed-turbinate whorls, suture narrow but not ap- 

 pressed, the color very dark olivaceous, the prominent sculpture paler; 

 nucleus minute, decorticated, but apparently smooth; spiral sculpture of 

 on the upper part of the last whorl four strong elevated cords with wider, 

 almost channelled interspaces, the two posterior cords more adjacent ; 



