AURICULA. Panama Shells. 209 



concave on the lower side, and on the upper side extended 

 to the summit of the aperture with a transversely ridged 

 surface. 



Mean divergence about 80 ; length .32 inch ; breadth .2 

 inch ; length of spire .09 inch. 



Station. Our specimens were found mostly on the short 

 suckers, which were growing up thickly beneath the mangroves, 

 near high water mark. 



Habitat. Panama ; C. B. A. ! 



We collected 74 specimens two and one-half miles east of 

 Panama. 



311. Auricula infreqiicsis. Nov. sp. 



Shell ellipsoidal : brown, with a pale ill-defined spiral band a 

 little below the suture : with fine stride of growth : apex acute : 

 spire with the outlines moderately curvilinear : whorls six, 

 obtusely shouldered, with a deep suture ; last whorl compressed : 

 aperture subelliptical, rather wide : labrum very thin : with two 

 plates, of which one is at the anterior part of the aperture and 

 is oblique, and the other is transverse and is at the middle. 



Mean divergence about 80 ; length .23 inch ; breadth .15 

 inch ; length of spire .1 inch. 



Station. Under stones, near high water mark. 



Habitat. Panama; C. B. A.! 



We collected 6 specimens, in company with Pedipes angulata, 

 at the base of the sea wall of Panama. 



312. Auricula Paiiamensis. Nov. sp. 



Shell long ovate : blackish red throughout except that the 

 plaits are white : smooth and shining, with a few microscopic 

 spiral striae near the apex : apex acute : spire with the outlines 

 very curvilinear over the middle whorls, and nearly rectilinear 

 on the lower whorls: whorls eight, convex, imbricately appressed ; 



