CYRENA, Panama Shells. 275 



449. Artemis saccata. 



Synonymy. 



Arthemis saccata Gould in Proc. Bost. Soc. Nat. Hist. p. 91. Nov. 1851. 

 Station. Unknown. 



Habitat. Mazatlan ; Lt. Green ! Gould. 



Panama ; C. B. A. ! 

 2 specimens were obtained. 



450. Gouldia Pacifica. Nov. sp. 



Shell subtriangular, but with the ventral margin well 

 excurved : the color varying in different specimens from dingy 

 white to pale brown, often tinged with red about the beaks, 

 with some narrow rays of brown, and rarely with short irregu- 

 lar lines of brown : with eight to twelve stout subequal concen- 

 tric ridges : sometimes radiately striated : beaks very acute and 

 closely approximate: posterior area moderately depressed: 

 lunule denned by a well impressed line, rising at the margin of 

 the valves : margin of the interior not crenulate. It is closely 

 allied to G. parva Ad. 



Length .22 inch ; height .19 inch ; breadth .09 inch. 



Station. Unknown. 



Habitat. Panama ; C. B. A. ! 



We collected 4 entire shells and 60 odd valves. 



451. Cyrena maritima. Nov. sp. 



Shell subtriangular, but with the ventral margin well 

 excurved, ventricose, thin : dingy white, more or less viola- 

 ceous in the posterior half: with an olivaceous coarsely striate 

 epidermis : with well impressed striae of growth : beaks very 

 prominent, approximate : umbones very prominent : with a 

 prominent posterior angle, and another less developed posterior 



