23 University of Washington Publications in Geology [Vol. I 



GENUS CARDIUM LINNEAUS 



CARDIUM OLDROYDI n. sp. 

 Plate VIII, Figures 3, 11 



Cardium brewerii Dickerson, 1915, Proc. Cal. Acad. Sci., Vol. V, No. 3, pi. 2, 

 figs. 3a, b. 



Description. Shell moderate in size, subovate, beaks central ; posterior mar- 

 gin nearly straight, rounding into the dorsal and ventral margins ; anterior and 

 ventral margins regularly rounded ; surface ornamented with about twenty-seven 

 wide, flat-topped, radiating ribs with interspaces about half the width of the ribs ; 

 on both sides of each rib at the angle is a series of delicate nodes which are con- 

 tinuous from the beaks to the ventral margin. On the umbonal area they are 

 minute, increasing in size downward ; on the portion of the shell below the middle 

 they are very conspicuous ; the first two or three posterior interspaces are 

 coarsely cross-striated, many begin to show a divided condition which ultimately 

 gives rise to the bi-pustulate character of the ribs. The ribs have the appearance 

 of being barbed. On one specimen several distinct, short, spiny tubercles occur, 

 situated along a faint mid-groove of the ribs. The whole sculpture is beautiful 

 and delicate. Anteriorly the ribs are often eroded and the presence of the fine 

 nodes obscure ; internal margin fluted or grooved. 



In shape this species is somewhat like C. brewerii Gabb but is more oval 

 than that form. The posterior umbonal slope is less sharp and the posterior area 

 less concave in C. oldroydi. The unique nodose character of the ribs with the 

 1 ossible development of tubercles makes this species distinct. 



Named in honor of Mrs. Ida Oldroyd of Leland Stanford University. 



Dimensions. Length 26 mm. ; height 25 mm. ; thickness 20 mm. 



Occurrence. At locality 329 (University of Washington Palaeontological 

 Collection) west bank of the Cowlitz River, near the town of Vader, Lewis 

 County, Section 28, Township 11 North, Range 2 West. 



GENUS PIT ARIA ROEMER 



PITARIA (Lamelliconcha) EOCENICA n. sp. 



Plate X, Figures 14, 16 



Description. Shell medium in size; ovate; beaks prominent, situated about 

 one-third of the distance from the anterior end; dorsal margin high; posterior 

 end sloping roundly to the ventral margin ; ventral margin regularly and broadly 

 rounded ; anterior end produced ; concave beneath the beaks ; lunule heart-shaped, 



