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University of California Publications in Geology [Vol. 7 



GLYCIMERIS MABYSVILLENSTS, n.sp. 

 Plate 14, figures la and 16 



Shell, small, subglobose, almost equilateral ; beak small, in- 

 curved and central. Cardinal margin, straight ; the anterior and 

 posterior margins, regularly rounded. Surface marked by prom- 

 inent concentric ribs. Hinge marked by eleven teeth. Area 

 trigonal, small. 



University of California Locality 1853. Named for the occur- 

 rence at Marysville Buttes in which the type specimen was found. 

 Dimensions : Height, 5mm ; length 5mm. 



NUCTJLA COOPERI. n.sp. 

 Plate 14, figures 2a and 2b 



Shell, small, rounded triangular; small rather prominent 

 beaks located about a third of the length from the anterior end 

 and inclined forward. Cardinal margin nearly straight, sloping 

 rapidly to the posterior margin ; anterior end truncated, ex- 

 eavated under the beaks, slightly concave and united with the 

 basal margin by a sharp angle; basal margin evenly rounded; 

 posterior end narrowly rounded. Surface marked by many 

 minute lines of growth and by small radiating ribs. Hinge 

 robust, pit, very small. This species resembles Nucula solitaria 

 Gabb of the Chico group closely, but the radiating ribs of this 

 form readily distinguish it. 



University of California Locality 1853. Named in honor of 

 Dr. J. G. Cooper, who first described species from this locality. 



Dimensions: Height. 6mm; length, 8mm. 



TELLINA SUTTERENSTS, n.sp. 

 Plate 14, figures 3a and 3b 



Shell, oblong, compressed, thin. Beaks prominent, being 

 located about one-third of distance from the anterior end. An- 

 terior and posterior extremities rounded; the anterior dorsal 

 margin slopes from the beaks more steeply than the posterior 

 dorsal margin. Surface marked by minute lines of growth. 



University of California Localities 1853 and 1856. Named for 

 the occurrence in Sutter County, California. 



Dimensions : Height, 6mm ; length, 8mm. 



