112 COLORADO FORMATION AND ITS INVERTEBRATE FAUNA, [bull.106. 



convex slopes, both in front and behind the beaks ; beaks very nearly 

 central and inconspicuous, being depressed and compressed. Surface 

 of casts smooth, but probably on well-preserved shells marked with 

 fine coucentric striae. Hinge and interior unknown, with the exception 

 of some appearances of lateral teeth seen in casts. 



"Length, 0.86 inch; height, 0.44 inch; convexity, 0.10 inch." 

 The name of this species was first used in a list of fossils from Coal- 

 ville, Utah, published in the Ann. Kept. U. S. Geo!. Sur. Terr, for 

 1872, but it was not then described. All the specimens yet found are 

 casts in sandstone that show neither the natural surface nor the inter- 

 nal features. It does not resemble any known form in the Cretaceous 

 of the interior region, but there is a closely related undescribed species 

 in the Ripley beds of Texas, and when describing it Prof. Meek pointed 

 out its resemblance to T. ashburneri which occurs in the Chico series of 

 California. 



Locality and position. — Whitish Cretaceous sandstone on East Canyon 

 creek, Wasatch range, Utah. The specimen figured is from the " sec- 

 ond ridge," at Coalville, Utah. 



Tellina (Paljeomgera?) whitei n. sp. 



PI. xxv, Figs. 4-7. 



Shell of medium size, inequilateral, subovate, moderately convex; 

 beaks rather broad and flat, situated behind the middle and directed 

 backward; posterior end descending abruptly from the beak in abroad 

 somewhat irregular curve to the base, where it is obscurely subangular; 

 cardinal margin in front of the beaks, straight, descending with a more 

 gentle declivity to the anterior end, which is regularly rounded and 

 slightly narrower than the posterior end; base nearly straight in the 

 middle, more strongly curved toward the ends. Surface marked by 

 fine concentric stria? and lines of growth. An obscure ridge extends 

 from the umbonal region near the margin of the valve to the postero- 

 basal angle, and a short distance in front of it the shell is slightly bent 

 to the right. One of the specimens shows traces of a few faint impress- 

 ed radiating lines near the posterior end. 



The ligament is rather prominent and there is a deep lanceolate area 

 in front of the beaks. The pallial sinus is broad and deep. 



Length of the larger type specimen, 35" ,rn ; height, 25 ,mn ; convexity 

 of both valves united, 12 mm . 



As neither of the two types shows the hinge the generic relations of 

 this species are doubtful, but the features above described are deemed 

 sufficient to warrant its assignment to the Tellinida',, and on account of 

 its general resemblance to Tellina (Palceomcera) inconspicua Forbes as 

 figured by Stoliczka 1 it is provisionally placed in the same subgenus. 



Locality and position. — In the Pugnellus sandstone on Williams creek, 

 Huerfano park, Colorado. 



> Cret. Pelec. of S. India, pi. 4, figs. 6-8. 



