DONAX. Panama /Shells. 277 



which is smaller and higher, at a depth of 5 fathoms in thin 

 mud ; Cuming ! Sowerby. 



The only living specimen which we found was buried one or 

 two inches deep in sand, on a sandy flat, near low water mark. 



Habitat. Gulf of Nicoya ; Cuming ! Sowerby : also Muller. 



Tumbez (for the var. above mentioned) ; Cuming ! 

 Sowerby : also Miiller. 



Peru and Central America ; Hanley. 



Punta St. Elena ; Jay. 



Panama ; C. B. A. ! 

 3 specimens were obtained. 



454. Donax assimilis. 



Synonymy. 

 Donax assimilis Hanley in Proc. Zool. Soc. Lond. p. 17. Mar. 1845. 



/Station. At about three quarters tide level, buried a few 

 inches deep in sand. It is frequently used for food by the 

 inhabitants. The regard which these mollusks have to a deter- 

 minate level, was shown by a method for finding them, which 

 was employed by a negro woman, who was seen several times 

 collecting them. Beginning below the level where they might 

 be found, the sand was scooped up with a calabash, in a line 

 running up the beach, until the shells were found. Then by 

 keeping to this level, every calabash full of sand yielded more 

 or less of the Donax. 



Habitat. Panama ; Hanley. 



Mazatlan ; Lt. Green 1 Mus. Essex Inst 



Panama ; C. B. A. 1 

 350 specimens were collected. 



455. Donax gracilis. 



Synonymy. 

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



