'336 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 40. 



rated by deep, rounded channels almost as wide as the keel. In addi- 

 tion 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 first, 22 upon the fifth, and 30 upon the penultimate post-nuclear 

 turn. The connections between the tubercles, both spiral and axial, 1 

 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 supra- 

 peripheral 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. Aperture 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 extends over the parietal wall. 



The two cotypes, Cat. No. 109512, U.S.N.M., were collected by Mrs/ 

 W. II. Eshnaur at Terminal Island, San Pedro, California. The one 

 has the nucleus and three post-nuclear whorls; the other has lost the 

 nucleus and has nine post-nuclear turns and measures: Length 5.2 

 mm., diameter 1.8 mm. 



Specimens examined. 



Catalogue 

 No. 



i 109512 

 56751 

 195179 

 14825 

 195180 

 737250 

 130584 

 32287a 

 322206 

 56006a 

 123401 

 109364 

 199179 

 153058 

 106504 

 32292 



Locality. 



Terminal Island, California 



Catalina Island, California 



San Pedro, California 



do 



White's Point, San Pedro, California 



San Pedro, California 



San Diego, California 



do 



do 



do 



do 



do 



do 



Government Jetty, San Diego, California. 



Point Abreojos, Lower California 



Todos Santos Bay, Lower California 



Number of 

 specimens. 



350 

 1 

 3 

 1 

 1 

 1 

 9 

 40 

 13 

 3 

 6 

 1 

 1 

 7 

 1 

 1 



1 Cotypes. 

 CERITHIOPSIS (CERITHIOPSIS) TUBERCULOIDES Carpenter. 



Plate 37, fig. 7. 

 Cerithiopsis tuberculides Carpenter, Cat. Maz. Shells, 1857, pp. 442-443. 



Shell elongate-conic. Nuclear whorls five, well rounded, smooth, 

 separated by a moderately constricted suture forming a well elevated 

 spire. Post-nuclear whorls moderately rounded, ornamented with 



