86 



PALJEONTOLOGY OF NLW-VORK. 



Posilion and loca'i/ij. In the shale below the ore bed ;it Wolcolt, Wayne county. 



{Slate CvlUclion ) 



477. 8. TELLINOMYA CURTA (n. sp.). 



PL. XXVII. Figs. 10 and 13. 



Shell ovate-rhombouhil, length once and a half the height ; anterior extremity short, abruptly 

 rounded ; beak elevated above the cardinal margin ; posterior extremity obliquely truncated ; 

 posterior umbonal slope angular or sub-carinated, with a sinus between it and the margin of 

 the shell ; surface marked by concentric undulations. 



This shell is readily tlistinguislied from any of those preceding, by the obliquely truncated 

 posterior extremity, and stronger folds upon the surface. The beak is also more elevated, 

 standing prominently out from the cardinal line. In the drawing of fig. 10, the beak is in- 

 correctly blended with the cardinal margin. 



Position and locality. In the shales beneath the ore bed at Wolcott, Wayne county. 



478. 4. ORTHONOTA CURTA. 



Pl. XXVII. Fig. 11 a, 6. 

 Orthonota curta. Hall, Geol. Rep. 4th District, 1843, pag. 76, fig. 1 



Shell sub-quadrangular, oblong, length from twice and a half to three times the height ; 

 posterior umbonal slope sub-carinated ; hinge-line straight ; anterior extremity short, con- 

 tracted in front of the beak, and rounded or sub-acute ; posterior extremity obliquely truncated ; 

 surface marked by prominent concentric folds, which are more conspicuous on the anterior 

 and central portions of the shell. 



The proportions of this, as well as the other species, are much altered by pressure, as 

 shown in the two specimens figured, which give the extremes noticed. The specimen fig. 11 

 a, however, retains more nearly its original form and propoi'tions, judging from other speci- 

 mens. It is readily recognized by the straight hinge-line and strong concentric folds. 



This species possesses the true characters of the genus Orthonota, as established by Mr. 

 Conrad. 



Fig. 11a. The right valve of a specimen of natural size and proportions. 

 Fig. 11 5. A specimen of the left valve, narrowed by pressure. 



Position and locality. In the shale below the ore bed at Wolcott, and in the upper green 

 shale at Rochester. (State Collection.) 



