1918] Van Winkle: Paleontology of the Oligocene 85 



ACMAEA CLARKI n. sp. 

 Plate VI, Figure 4 



Description Shell small, high and thin; smooth except for concentric lines 

 of growth; apex situated about midway between the anterior and posterior ends. 



Acmaea clarki differs from Acmaea dickersoni in being on the average slightly 

 higher; the apex more central and in the absence of radiating ribs. 



Dimensions Altitude 8 mm.; diameter of base 10 mm. by 12 mm. 



Occurrence At locality 161 (University of Washington Paleontological Col- 

 lection) situated about one mile west of Oakville on the Northern Pacific Railway. 



Horizon Lowermost Oligocene; Barbatia merriami Zone. 



GENUS EULIMA RISSO 



EULIMA SMITHI n. sp. 

 Plate VII, Figure 22 



Description Shell minute, conical in outline and smooth except for very faint 

 lines of growth; whorls seven in number; spire about twice the length of the body 

 whorl: suture distinct, linear and appressed; aperture oval; canal short, broad and 

 twisted to the left ; outer lip thin ; inner lip slightly calloused and reflected. 



Dimensions Altitude 3 mm.; altitude of spire 1.5 mm.; maximum diameter 

 of shell 1 mm.; angle of spire 37. 



Occurrence At locality 330 (University of Washington Paleontological Col- 

 lection) situated at the Greece ranch, four miles east of Vader, on the east bank of 

 Cow 7 litz River, in Section 25, Township 11 North, Range 2 West. 



Horizon Lower Oligocene; lower phase of Molopophorous lincolnensis Zone. 



EULIMA HILTOXI n. sp. 

 Plate VII, Figure 12 



Description Shell minute, slender, thin and elongate; smooth except for very 

 faint lines of growth; whorls seven in number; suture distinct linear and very 

 appressed; aperture semi-oval as observed on other specimens. 



This species differs from Eulima smithi in that the former is conical. Eulima 

 hiltoni averages much longer and is more slender. 



Dimensions Altitude of shell 4 mm. ; altitude of spire 3 mm. ; maximum 

 diameter 1.5 mm.; angle of spire 25. 



