3og Pamma Shells, arcid^. 



5flJ?i«f;.— Fa»am^ ; Oumisg I S0wer^)y : also MUller. 



Panama ; Deshayes : also Hanley. 



Panama ; 0. B. A, I 

 10 odd valves were found. 



411. Pecfunculiis as$imilis, 



Syncmymy. 



Pectunculus assimilis Sowb. in Proc. Zool. Soc. Lond. p. 196. Dec. 1832. 



Miill. Syn. Test. Viv. p. 189. 1830. 



— — „-^ Reeve Conch. Icon, pi 4. f. 15. Mar. 1843. 



__, Orb. Voy. Amer. Mend. MoU. p. 629, 1846, 



In the number, width, and form of the cross bands of brown 

 our specimens are so variable that no two axe alike, and two 

 of them have most of the ground color of a greyish blue. In 

 respect of coloring, therefore, the species does not appear to be 

 well distinguished from P. inaqmlis. Nor ia the distinction in 

 sculpture much more constant. 



Station. — In sandy mud and gravel, in from 8 to 12 fathoms ; 

 Cuming I Sowerby : also Eeeve. 



Our specimens were found under stones, in calcareous gravel, 

 between one quarter tide and low water mark. 



Habitat. — Puerto Portrero, Bay of Guayaquil, Central Ame- 

 rica; Cuming 1 Sowerby: also Miiller: also 

 Eeeve : also Orbigny, 

 Guayaquil ; Jay. 



Mazatlan ; Lt. Green I Gould MSS. 

 Panama ; 0. B. A. I 

 2Q specimens were collected on the reef. 

 A common ambiguity again appears in Mr. Sowerby's state- 

 m.ent \ since the Bay of Guayaquil (and Puerto Portrero ?) ia not 

 in Central America, is the latter mentioned as a third locality ? 



