QUATERNARY FOSSILS. 335 



which have occurred in the Quaternary clays of southern 

 Greenland, a list of which is here given. 



Peden islandicus, Mya truncata, 



Leda minuta, Mya arenaria, 



Mytilus edulis, Panopesa norvegica, 



Modiolaria discors, Saxicava arctica, 



Astarte semisulcata Leach, Tellina calcarea, 



Astarte corrugata Brown, Tellina fragilis, {gronlan- 



Cardium ( Aphrodite ) dica), 



gronlandicum, Natica clausa B. & S., 



Cardium islandicum, Littorina gronlandica, 



Cryptodon fiexuosus, Fusus despectus Linn, 



Cyrtodaria siliqua, Margarita glauca, 



Fusus gracilis Da Costa. 



By reference to the lists of fossil shells found in the 

 clays of the New England and Labrador coasts it will be 

 seen that during the Quaternary of the French and Scan- 

 dinavian geologists, oi- post-pliocene period of Lyell, the 

 distribution of marine animals was governed by the same 

 laws as at the present day. In going southward from 

 Labrador to New York the seas became warmer the more 

 they came in contact with the heated waters of the Gulf 

 Stream, whose influence was slightly exerted on the 

 coast of New England during the glacial period. The 

 climate of New England was not purely arctic, but 

 rather sub-arctic, where now it is " boreal." While this 

 period was characterized by the wide distribution of 

 what are now purely arctic or circumpolar species, there 

 were also intermingled boreal or Acadian forms. Thus 

 the arctic Leda arctica, Pecten gronlandicus, Serripes 

 gronlandtcus, Pandorina arenosa, and Fusus tornatus 



