no. 1823. MOLLUNKti OF THE GENUS CERITHIOPSIS— BARTSCH. 



335 



that separating the first supraperipheral cord from the median spiral 

 cord and, like it, crossed by the continuations of the axial ribs. Base 

 short, well rounded, marked by a broad, spiral cord which is truncated 

 posteriorly and slopes gently anteriorly toward the shallow, well- 

 marked groove which separates it from the base proper. Entire sur- 

 face of spire and base marked by numerous, very slender, incremental 

 lines. Aperture irregularly oval, very strongly channeled anteriorly; 

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

 within, rendered decidedly sinuous at the edge by the external sculp- 

 ture; columella stout, moderately long, the edge reflected; parietal 

 wall glazed with a thin callus. 



The above description is based upon the two cotypes which, together 

 with 130 specimens, are registered as Cat. No. 109510, U.S.N.M., and 

 come from Terminal Island, California. One of these specimens is a 

 young individual consisting of the three nuclear whorls and six post- 

 nuclear whorls; the other is an adult which has lost the nuclear whorls 

 and has ten post-nuclear whorls which measure: Length 8.1 mm., 

 diameter 2.8 mm. 



Named for the late Dr. Philip P. Carpenter. 



Specimens examined. 



Catalogue 

 No. 



i 109510 



109511 



173088 



73725 



195178 



152758 



159330 



134857 



' 15653 



i 130584 



56005 



32219 



32287 



130315 



3566 



32220 

 56006 

 123401 



Locality. 



Terminal Island, California. 



do 



....do 



San Pedro, California 



White's Point, San Pedro Bay, California. 



Alamitos Bay, California 



San Diego, California 



....do 



.do. 



San Diego, California (on sponge). 



San Diego, California 



do 



.do. 



False Bay, San Diego, California 



San Diego Bay, California (3 fathoms, sand and shell bottom, 



bottom temperature 58°) 



San Diego, California 



....do 



San Diego, California (living on sponges) 



Number of 

 specimens. 



132 



1 



21 



1 



2 



35 



5 

 3 

 1 

 4 



17 



15 



114 



1 



1 

 48 

 18 



1 Cotypes. 

 CERITHIOPSIS (CERITHIOPSIS) PEDROANA Bartsch. 

 Plate 38, fig. 2. 

 Cerithiopsis pedroana Bartsch, Proc. U. S. Nat. Mus., vol. 33, 1907, pp. 181-182. 



Shell small, slender, dark brown. Nuclear whorls three, yellowish- 

 white, smooth. Post-nuclear whorls strongly differentiated from the 

 nuclear ones, showing the sculpture characteristic of the adult shell 

 from the very beginning. This sculpture consists of three equally 

 spaced tuberculate spiral keels between the sutures, the posterior one 

 of which is slightly smaller than the other two. These keels are sepa- 



