stanton.] TELLINIDiE. 113 



Tellina? subalata Meek (sp.). 

 PL xxv, Fig. 9. 



Cyprimcra subalata Meek, 1873, Ann. Ropt. U. S. Geol. Sur. Terr, for 1872, p. 476. 

 Cyprimeriaf subalata Meek, 1877, U. S. Geol. Expl. 40th Parallel, vol. IV, Pt. 1, p. 158, PL 

 15, Fig. 7. 



Eevised description : 



"Shell transversely broad- subovate or subelliptic, strongly com- 

 pressed; extremities rather narrowly and nearly equally rounded; 

 basal margin forming a regular semielliptic curve, being most promi- 

 nent along the middle, and rounding up gradually and equally into the 

 anterior and posterior lateral margins; dorsal margin sloping from the 

 beaks, the posterior slope being more convex in outline than the ante- 

 rior; beaks small, scarcely projecting above the hinge-margin, very 

 nearly or exactly central, and almost entirely without obliquity. Sur- 

 face apparently smooth, or only showing very fine, obscure, concentric 

 strife. (Hinge and interior unknown.) 



"Length, 1.22 inches; height, 0.90 inch; convexity of left valve, only 

 about 0.12 inch." 



The type specimen bears the label Tcllina (Arcop.) subalata in Mr. 

 Meek's handwriting, but after comparing it with Cyprimeria depressa 

 Conrad he concluded that it belonged to the same genus on account of 

 a resemblance in form. The additional material recently collected at 

 Coalville, Utah, is in the form of casts, one of which retains impressions 

 of two cardinal teeth, showing that it belongs to the Tellinidse rather 

 than the Veneridae. 



Locality and position. — The type is from whitish Cretaceous sand- 

 stone, East Canyon creek, Wasatch range, Utah, where it is asso- 

 ciated with Trigonarca obliqua and other Colorado species. At Coal- 

 ville it was found in the sandstone of the " third ridge," which is 

 believed to belong to the Montana formation. 



i t< 



Tellina?? isonema Meek. 

 PL xxv, Fig. 8. 



Tellina f t isonema Meek, 1877, U. S. Geol. Expl. 40th Parallel, vol. iv, pt. 1, p. 156, PL 

 15, Fig. 6. 



Original description : 



"Shell transverse, elliptic-subtrigonal in outline, compressed, and 

 nearly or quite equilateral; anterior margin narrowly rounded; base 

 forming a semi-elliptic curve; posterior end narrowly rounded or sub- 

 angular at the termination of a slight, oblique flexure of the valves ; 

 dorsal margin sloping from the beaks to the extremities, with a moder- 

 ately convex outline; beaks almost central, rather small, and project- 

 ing a little above the cardinal margin, incurved with scarcely any visi- 

 ble obliquity; hinge and interior unknown. Surface ornamented by 

 Bull. 106 8 



