214 K. Y. State Museum of Natural History. 



Surface of the valve and spine black, shining, smooth to the eye, 

 but under the magnifier slightly elevated inosculating lines appear, 

 radiating from the muscle spot ; the interspaces are minutely punctate. 



It is associated with Leperditia fdbulites and varieties of L. Can- 

 adensis. 



Formation and locality. Birdseye and Black River limestones, 

 Buck's Quarry, Russia, Herkimer Co., N. Y. 



