286 University of California Publications in Geology [Vol. 7 



OLIVULA MARYSVILLENSIS, n.sp 

 Plate 13, figures la and 16 



Whorls number six, the body-whorl being four times as long 

 as the spire. The body-whorl is decorated by distinct, close 

 longitudinal and revolving striae, and four prominent slightly 

 oblique revolving ribs on the lowermost third; spire covered by 

 a longitudinally striate deposit, angulated at suture of body- 

 whorl forming a raised band just below the suture. Aperture, 

 channeled posteriorly. Posterior portion of inner lip covered by 

 a callus which extends to top of spire. The lower portion of 

 the columella is marked by five small but prominent very oblique 

 plaits. Outer lip, thin and straight. 



Only one small specimen was found at University of Califor- 

 nia Locality 1853. The only noteworthy difference between this 

 species and Olivula staminea Conrad of the Alabama Claiborne 

 is that the revolving ribs on the body-whorl are less oblique than 

 those of 0. staminea. 



Dimensions: Length, 10mm; width of body whorl, 4mm. 



OLIVERATO CALIFORNICA Cooper 

 Plate 13, figures 4a and 4b 



Oliverato calif arnica. — Cooper, J. G., Catalogue of California Fossils, 

 Bull. 4, California State Mining Bureau, p. 43. 1894. 



"About half of spire (the nuclear whorls) invisible in adult; mouth 

 with lips nearly parallel at middle; narrower at ends in the young, with 

 about ten faint ridges along columella, not passing inside; no umbilicus. 

 Dorsal surface marked by ridges from irregular thickness of the callus, 

 and a deep oblique furrow running from the anterior notch toward the 

 left, as in Pseudoliva, etc. Parallel to this, about six light ridges, remain 

 permanent behind it, thickened but not obscured by callus. General 

 form becoming more ovate with age, but always narrower in front. 

 Length, about 1.50 inch; breadth, about 0.85; mouth, 1.12 inch long, 0.50 

 wide. Eight specimens examined. 



' ' Four of the specimens are polished and colored a fine brown, just 

 as in the living Erato vitellina. This color is confined to a thin outer 

 layer of the callus, as shown in the dorsal figures. ' ' 



Dimensions : Length, 38mm ; width of body-whorl, 23mm. 



This form occurs at nearly all the Eocene localities in the 

 Marysville Buttes. It is also found on the Umpqua River in 

 Oregon and at University of California Locality 195, "Concord 



