gO CONCHOL OG TA CEStE RGA 
the ligament; beaks small, undulated; yellowish-brown, 
with dark-green rays; nacre inclined to pale salmon 
color; cardinal teeth double, sometimes trifid, long, 
compressed, oblique. “Eymz5 a .2.25) 1. .8, inches: 
Station, Schuylkill River, Chester County ; common. 
U. nasutus, Say, Nich. Encyc., 1st Amer. Ed., 1816. 
U. nasutus. 
Fig, 186, 

Shell, thin, oblong, rounded before, rostrate posteri- 
orly; fuscous, radiate with green, behind the middle; 
beaks small, undulate; within bluish-white; cardinal 
teeth small, oblique, ‘crenate. HH. 1-25, W220, 175, 
inches. 
Station, Schuylkill River, Chester County. 
U. Fisherianus, Lea, Tr. Amer. Phil. Soct., VI., 1834. 
U. Fisherianus. 
Fig. 187, 

Shell, thin, compressed; beaks very near the anterior. 
