Vol. IV] ANDERSON AND MARTIN— NEOCENE RECORD 71 



Occurrence : — Not common in the middle portion of the 

 Santa Margarita (San Pablo) foniiation in the eastern part of 

 San Luis Obispo County, California, locality 58. 



This species can be distinguished by its peculiar tabulation 

 and spiral sculpture. 



Type: — No. 150, Cal. Acad. Sci., San Luis Obispo County, 

 California ; in the south bank of a small creek in the N. E. Vi 

 of Sec. 22, T. 29 S., R. 17 E. 



Genus CERITHIUM Brug. 

 Cerithium arnoldi, new species 



Plate 7, figure 12. 



Shell conical, elongate, small, with nine or ten closely ap- 

 pressed whorls; spire high; apex acute; whorls nearly flat, 

 crossed by numerous irregular wavy, axial ribs which are ren- 

 dered slightly nodose by the spiral cords ; the spiral sculpture 

 on the penultimate whorl consisting of three or four cords 

 separated by wider interspaces which carry small secondary 

 spiral threads ; body-whorl carrying seven or eight of the larger 

 spiral cords between each two of which there are three inter- 

 calary lines, the middle one slightly larger than the two on 

 either side; base flattened producing a distinct angulation on 

 the anterior portion of the bod3''-whorl ; aperture subquadrate ; 

 lips simple ; canal very short. 



Dimensions : — Altitude of the type, 19 mm. ; diameter of the 

 last whorl, 7.5 mm, 



Occurrence : — A single specimen from the lower Miocene of 

 Kern River, locality 64. 



Type: — No. 151, Cal. Acad. Sci., Kern County, California, 

 in the bottom of a small canyon about P/4 miles due north of 

 Barker's ranch house. 



Named for Ralph Arnold in recognition of his valuable con- 

 tributions to Tertiary paleontology. 



Genus ARGOBUCCINUM Morch 

 Argobuccinum dilleri, new species 



Plate 4, figure 7. 

 Shell large, solid, with nine or ten strongly sculptured 

 whorls ; spire high ; whorls convex, tabulated, sculptured with 



