268 PALjEONTOLOGY OF NEW YORK. 



MmilOLA (MVTILOPS) MKTKLLA. 



I'l.ATE XXXIII, I'lGS. ■-'3,24; AXI. IM. ATK I.XXXMl, Klti li 



Modiola iiutclla, IIai.l. Prelim. Nolii'o Lain. Hhp\U. etc., jit. 2, i>. 1. IWiO. 



ilytiUqts (Mo(liolu) iip:tcll,i. Hall. P:il. N. Y.. vol. v, pt. I. Pl.itrs :un\ Kxi>lanatioiis: PI. :!:!. i\-s~. -':!. -.'I 



Jan.. 1SS:J. 



SuELi. large ; body naiTow elliptical, sub-arcuate, ol)li<iuely truncate on the 

 anterior dorsal side; length more than twice tiie height; ventral margin 

 gentl\- curving, nearly straight for three-luurths of the length, thence 

 abruptly rounded at the posterior extremity ; dorsal margin very gently 

 curving to the extremity of the hinge-line. 



Valves equal, depressed-convex at the posterior end, becoming gradually 

 more convex to a point anterior to tlie middle of the length, and gibbous in 

 the umbonal region. 



Hinge-line obli(iae, about ecpial to the iieiglit of the valve. Beaks small, 

 appressed. 



Test thin, marked b}- concentric striae. 



Liscamental area marked bv two slender grooves. Other interior characters 

 unknown. 



A specimen has a length ol' -"tT mm., height 2o mm., and hinge-line 24 mm. 



This species dift'ers from M. prcecedens in its larger form, which is less 

 expanded posteriorly, less angular and gibbous along the umbonal slope, and 

 without radii on tiie surface so far as can be determined in the specimens. 



Formation and localities. In a conglomerate of the ('luMuung grouj). at 

 Panama, and in a liouliler of similar rock on tiie road from Ellington to Cherry 

 cieek, Chautauqua county, N. Y., and at Warren, Pa. 



