THE EUROPEAN SEAS. 



253 



than would be brought about by the shifting of 

 the Lusitanian province northwards for its entire 

 breadth. 



The forms of the Faluns of Bordeaux and Tou- 

 raine were not local or exceptional assemblages; they 

 indicate directly that for a broad expanse in latitude 

 the Atlantic, at that early stage, had a fauna of a 

 more southern aspect than it has now, and they sug- 

 gest further, that like general characters, modified 

 by the ordinary rate of change, were maintained in 

 its extension northwards. Although there are no 

 broad areas which present remains of these older 

 sea-beds, except at the entrance into the Channel 

 (in the Cotentin), yet traces of the fauna, and of 

 the period, are to be found in those outlying Lusi- 

 tanian species which are to be met with about the 

 Channel Islands, our own southern and south- 

 western coasts, or on those of the Atlantic border 

 of Ireland. 



It has been shown, by numerous illustrations, 

 derived from various classes of marine animals, that 

 the fauna of the Atlantic coasts of Europe is, for 

 the most part, a complex assemblage ; that from 

 our own Celtic province, as low as the Canaries and 

 the Mediterranean, it is composed of two distinct 

 elements, a northern and a southern ; and that the 

 members of this middle group may be severally 

 referred back to their original homes, whether 

 north or south. 



It is to be remarked, that the northern consti- 



