THE EUROPEAN SEAS. 



109 



as Patella pellucida, Velutina laevigata, Trochus 

 tumidus and cinerarius, Lacuna puteolus, Littorina 

 littoreus and rudis, Purpura lapillus, Mactra trun- 

 cata, Tapes pullastra and Pecten tigerinus. Now 

 it is very important to note that the majority of 

 these are characteristic, and mostly gregarious, spe- 

 cies of the Littoral and Laminarian zones ; species, 

 moreover, which could only be transmitted along 

 coasts presenting a line of rock or hard ground ; 

 and that they are univalves, which, as a general 

 rule, are less widely-diffused shells than bivalves. 

 Mr. Mac Andrew expresses his conviction that " the 

 marine fauna of Vigo, so far as the mollusca are 

 concerned, is more nearly related to that of the 

 British Isles than to that of the region in which it' 

 is situated." Among its more remarkable produc- 

 tions is a large reversed Fusus, which, though dif- 

 fering in some of its features from the fossil Fusus 

 contrarius, nevertheless so closely resembles some 

 varieties of that curious shell, that it is hard to 

 believe it to be other than the same species slightly 

 modified. The importance of the existence of a 

 British colony, so to term it, of littoral shell-fish 

 on the deep bays of Gallicia, depends on the geolo- 

 gical bearing of the fact. It is certainly a most 

 striking circumstance that we should find these 

 creatures living on the coast of Spain, only on its 

 most extreme western region, and in juxtaposition 

 with the sub-alpine flora of the Asturian type, 

 which is partially present also on the western coast 



