48 



nat mus pr 33:177-183. 



Numbers 565-573 are described in this paper. 



565 Seila montereyensis 



Monterey, Cal., to Todos Santos bay, Baja Cal. (Hemphill). 



566 Bittium (Stylidium) eschrichti icelum 



Neah bay, Wash., Monterey, Cal. (R. E. C. Stearns). 



567 B. Eschrichti montereyensis. Monterey, Cal. 



568 Bittium esuriens multifilosum 



Whorls 10, length 9.2, diameter 3 mm; 7 spiral keels between 

 the sutures on the whorls of the spire. 



Type locality: — White's Point, San Pedro, Cal. (Mrs. Old- 

 royd). Also from Monterey and Catalina Island. 



569 Bittium tumidum 



Type locality: — Monterey, Cal. (Canfield). 



570 Bittium quadrifilatum ingens 



Type locality: — Monterey, Cal. 



571 Cerithiopsis cosmia 



Monterey, Cal. south to Todos Santos bay, Baja Cal. (Stearns). 



572 Cerithiopsis (Cerithiopsis) pedroana 



"Shell small, slender, dark brown. Nuclear whorls 3, yellow- 

 ish-white, smooth. Post-nuclear whorls strongly differentiated 

 from the nuclear ones, showing the sculpture characteristic of the 

 adult shell from the beginning. This sculpture consists of 3 

 equally spaced tuberculate spiral keels between the sutures, the 

 posterior one of which is slightly smaller than the other two. 

 These keels are separated by deep, rounded channels almost as 

 wide as the keel. In addition there are many low, rather broad 

 axial ribs, the intersections of which with the keel form the 

 tubercles. About 20 of them occur upon the 1st, 22 upon the 5th, 

 and 30 upon the penultimate post-nuclear turn. The connections 

 between the tubercles, both spiral and axial, are about equal, 

 inclosing deep, squarish pits. In addition to the above sculpture 

 the entire surface is marked by fine spiral lines and lines of 

 growth. Sutures strongly marked, constricted, showing the 

 peripheral keel in the later whorl. Periphery marked by a broad, 

 low, rounded keel. Another of equal width is located upon the 

 middle of the base. The sulcus which separates these keels and 

 the supraperipheral sulcus are of equal width; both are crossed 

 by the weak continuations of the axial ribs, which gradually 

 weaken as they pass toward the columella. The basal keel is 

 separated from the columella by broad, shallow grooves. Aper- 

 ture irregularly oval, decidedly channeled anteriorly, outer lip 

 thin, rendered sinuous by the external keel; columella stout and 

 somewhat twisted, with a strong callus on its inner edge that ex- 

 tends over the parietal wall." — Bartsch, U. S. nat mus pr 40: 

 335. Also 33:181-182. 



Type locality: — Terminal Island, Cal — Point Abreojos, Baja 

 Cal. 



573 Metaxia diadema 



Monterey, Cal., to San Diego, Cal. (F. W. Kelsey). 



