CREPIDULA. Panama Shells. 233 



these writers are correct, we ought to find the characters always 

 graduating into those of other species, according to the position 

 of the shell. 



Hahitat. — Ilva ; Gualteri. 



Seas of Barbary ; Linnaeus : also Gmelin : also 



Lamarck. 

 In nearly all the Mediterranean; Deshayes. 

 Mediterranean ; Jay. 

 Bays of Tunis and Algiers ; McAndrew ! 

 Sicily ; C. B. A. 

 Mediterranean and Seas of Senegal; Potiez and 



Michaud. 

 Maine; Mighels! 



Massachusetts ; Gould I also C. B. A. I 

 New York harbor ; C. M. Wheatley 1 

 New Jersey ; Say. * ' 



Maryland, Carolina, Georgia, and East Florida; 



Say! 

 Jamaica ; 0. B. A. ! 

 I. of Chiloe and Panama; Cuming 1 Broderip; 



also Mtiller. 

 Panama ; C. B. A. ! 

 In the United States, Maine appears to be the northern limit 

 of the species : Dr. Mighels says, " I have never found but one 

 individual of this species in Casco Bay [Maine] ; this had 

 located itself within the mouth of a dead Biuxinum undatum." 

 In Massachusetts, we have only found one specimen north 

 of Cape Cod ; this was on Chelsea Beach. But south of Cape 

 Cod the species is common. In Jamaica, it is common in the 

 Bay of Port Eoyal. At Panama we collected 35 specimens. 

 This species is thus found to inhabit the following distinct 

 marine zoological provinces : — 



1. The Mediterranean. 



2. Bast side of North America, north of Cape Cod. 

 3 It 11 " " middle regions. 



JULY, 1858. 59 Ami. Ltc. Nat. Hut. 



