1 ^^ CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



shoulder located one-third of a whorl length below the suture ; 

 body-whorl marked by nodes which vary in strength with dif- 

 ferent individuals, and shouldered about one-sixth of a whorl- 

 length below the suture ; concave space between the suture and 

 the shoulder marked by about twelve spiral threads ; area below 

 the shoulder marked by spiral lines of variable strength and by 

 a flat-bottomed sulcus located half the whorl-length below the 

 shoulder; outer lip thin, dentate and lirate within; inner lip 

 covered by a thin callus ; umbilicus subimperforate ; canal short, 

 twisted to the left. 



Dimensions : Length of figured specimens, 40mm ; width of 

 body- whorl, 17mm. 



This species is easily distinguished from 5. sutterensis Dick- 

 erson, with which it is associated, by its greater length, by its 

 more pronounced spiral ribbing, and by its greater nodosity. 



Type: — No. 247, Cal. Acad. Sci. Locality 25, Roseburg 

 Quadrangle, Oregon, near the center of Sec. 19, T. 26 S., R. 

 3 W., on the east bank of Little River at its confluence with 

 the Umpqua, underneath the bridge at that point. Coll., F. M. 

 Anderson and Bruce Martin. 



Named for Dr. Bruce Clark, Instructor in Invertebrate 

 Paleontology, University of California. 



PSEUDOLIVA DILLERI, new species. 

 Plate 12, figures la, lb, U, Id. 



Shell biconical; whorls five; spire of moderate height, with 

 conical nodose whorls ; suture wavy, indistinct, and bordered by 

 a nodose rim on the succeeding whorl ; body-whorl marked by 

 two angulations, both being nodose, but the lower one the 

 stronger; a nearly flat, narrow horizontal space just below the 

 suture rim, this area marked, in addition to spiral lines, by the 

 backward bending lines which mark the former position of a 

 sharp V-shaped posterior sinus; a slightly nodose shoulder 

 terminating this narrow shelf of the body-whorl; from this 

 shoulder the shelf sloping downward to a point a third the 

 length of the body- whorl where another occurs; this second 

 angulation ornamented by prominent rounded tubercules about 

 twelve in number ; space between this angulation and the end of 

 the short, slightly-twisted canal marked in its midportion by a 

 deeply impressed groove and b}^ numerous fine spiral lines; a 



