186 Panama Shells. tbochid^. 



261. Titrinella minuta. Nov. sp. 



Shell discoidal : dingy white, shining : with excessively 

 minute transverse striae : apex obtuse : spire scarcely elevated J 

 whorls nearly three, depressed above, with a well impressed 

 suture ; last whorl much depressed, subangular at the periphery : 

 aperture rather large, orbicular: labrum slightly thickened: 

 umbilicus rather deep, nearly covered. 



Mean divergence about 170° ; greatest breadth .042 inch ; 

 least breadth .036 inch ; height .017 inch. 



Station. — Unknown. 



Habitat. — Panama ; 0. B. A. I 



4 specimens were found in the calcareous sand. 



262. Titrinella modesta. Nov. sp. 



Shell discoidal : dingy white, translucent : with a spiral 

 elevated line next below the suture, and a spiral keel around 

 the umbilicus ; with few microscopic spiral striae about the 

 periphery of the last whorl : apex not prominent : spire a little 

 elevated and regularly convex : whorls three and one-half, with 

 the suture distinct : aperture orbicular : umbilicus deep. 



Mean divergence 170° : greatest breadth .06 inch ; least 

 breadth .05 inch ; height .028 inch. 



Station. — Unknown. 



Habitat. — Panama ; C. B. A. ! 

 1 specimen was obtained. 



263. Titrinella Panaincnsis. Nov. sp. 



Shell subdiscoidal : white : with a stout spiral keel on each 

 side of the periphery of the last whorl, and two others on the 

 lower side of the shell, of which one next to the umbilicus is 

 slightly prominent ; with transverse rather distant curved ribs : 

 apex obtuse : spire convex, but little elevated : whorls a little 



