278 Panama Shells. TELLENIDJE. 



Station. Unknown. 



Habitat. Bay of Guayaquil, and of Caraccas, Chiriqui ; 



Cuming! Hanley. 

 Panama ; C. B. A. ! 

 20 odd valves were taken on the beach west of Panama. 



456. Donax navicula. 



Synonymy. 



Donax navicula Hanley in Proc. Zool. Soc. Lond. p. 15. Feb. 1845. 

 Station. Unknown. 



Habitat. Gulf of Nicoya; Cuming! Hanley. 



Panama ; E. Jewett ! Gould MSS. 



Panama ; C. B. A. ! 

 3 specimens were obtained. 



457. Donax rostratu. Nov. sp. 



Shell elongated, inequilateral, rostrated anteriorly ; ventral 

 edge excurved along the middle, anteriorly rectilinear ; anterior 

 margin very oblique, nearly rectilinear, forming with the ventral 

 edge a rostriform extremity : purple and dingy yellowish brown, 

 more or less in ill denned zones ; interior with the same colors 

 not in zones : posteriorly and near the beaks smooth and shin- 

 ing ; with rather distant very fine radiating striae over the 

 middle of the disc ; striae coarser anteriorly, more distant next 

 behind and more crowded before the umbonial angle ; the latter 

 are slightly rugose : beaks small, prominent : umbones pro- 

 minent ; with a very sharp angle separating a concave anterior 

 surface ; within slightly radiately striated ; with the anterior and 

 ventral margins crenulated, more coarsely and deeply at the 

 anterior extremity : with a prominent lateral tooth on each 

 side of the cardinal teeth. It somewhat resembles D. cardinatus 

 Hanley. 



Length 1.6 inch ; height 1.15 inch ; breadth .8 inch. 



