314 PALEONTOLOGY OF NEW YORK. 



Formation and locality. In the upper beds of limestone, at the Falls of the 

 Ohio, of the age of the Hamilton group, near Louisville, Ky. 



NucuLA Neda. 



PLATE XLV, FIGS. S, 4. 



Nucuia Neda, Hall and Whitkikld. Twenty-fourth Ann. Rep. N. Y. State Mus. Nat. Hist,, p. 191. 1872. 

 " " " " Hall. Pal. N. Y., vol. v, pt. 1. Plates and Explanations: PI. 45, 



figs. 3, 4. 1883. 



Shell of medium size, rhomboid-ovate, cuneate, length about one-fifth greater 

 than the height ; basal margin broadly rounded ; cardinal margin sloping to 

 the anterior and posterior extremities, which are abruptly rounded. 



Valves gibbous, with the umbones ventricose. 



Beaks a little more than one-third the length of the shell from the anterior 

 end, prominent and incurved. 



The surface has been marked by fine, concentric striae. 



The cast shows strong anterior and posterior muscular impressions, with 

 three or four umbonal muscular scars and a narrow protractor scar just within 

 the cardinal line, and anterior to the posterior muscular area, as usual in the 

 genus. 



The number of teeth cannot be determined, but there are as many as six 

 or eight on the posterior side, with a distinct ligamental cavity, in the cast, 

 beneath the beak. 



The specimen described has a length of 21 mm., and a height of 17 mm. 



This species is of the size and form of Nucula levata, of the lower Silurian 

 rocks, and differs but little from Nucula bellistriata, of Conrad. 



Formation and locality. In the hydraulic limestone of the age of the Hamil- 

 ton group, near Louisville, Ky. 



